# EDGAR Filing Document

**Accession Number:** 0001120924
**File Stem:** 0001193125-25-144374
**Filing Date:** 2025-6
**Character Count:** 161988
**Document Hash:** 89c69cb0c792eca8bb55b63becf5ac76
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-25-144374.hdr.sgml**: 20250623

**ACCESSION NUMBER**: 0001193125-25-144374

**CONFORMED SUBMISSION TYPE**: N-CSRS

**PUBLIC DOCUMENT COUNT**: 16

**CONFORMED PERIOD OF REPORT**: 20250430

**FILED AS OF DATE**: 20250623

**DATE AS OF CHANGE**: 20250623

**EFFECTIVENESS DATE**: 20250623

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** T. Rowe Price QM U.S. Bond Index Fund, Inc.
- **CENTRAL INDEX KEY:** 0001120924

**ORGANIZATION NAME:**
- **EIN:** 522273334
- **STATE OF INCORPORATION:** MD
- **FISCAL YEAR END:** 1031

**FILING VALUES:**
- **FORM TYPE:** N-CSRS
- **SEC ACT:** 1940 Act
- **SEC FILE NUMBER:** 811-10093
- **FILM NUMBER:** 251063493

**BUSINESS ADDRESS:**
- **STREET 1:** 1307 POINT STREET
- **CITY:** BALTIMORE
- **STATE:** MD
- **ZIP:** 21231
- **BUSINESS PHONE:** 410-345-2000

**MAIL ADDRESS:**
- **STREET 1:** 1307 POINT STREET
- **CITY:** BALTIMORE
- **STATE:** MD
- **ZIP:** 21231

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** T. Rowe Price U.S. Bond Enhanced Index Fund, Inc.
- **DATE OF NAME CHANGE:** 20110509

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** T. Rowe Price U.S. Bond Index Fund, Inc.
- **DATE OF NAME CHANGE:** 20051028

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** T ROWE PRICE US BOND INDEX FUND INC
- **DATE OF NAME CHANGE:** 20000802

## Series and Classes Contracts Data

### T. Rowe Price QM U.S. Bond Index Fund (Series ID: S000002166)

| Class ID   | Class Name                                    | Ticker Symbol   |
|:---|:---|:---|
| C000005563 | T. Rowe Price QM U.S. Bond Index Fund         | PBDIX           |
| C000222342 | T. Rowe Price QM U.S. Bond Index Fund-Z Class | TSBZX           |
| C000222343 | T. Rowe Price QM U.S. Bond Index Fund-I Class | TSBLX           |

?xml version='1.0' encoding='ASCII'? QM U.S. Bond Index Fund_UBX_F134-052

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

### FORM N-CSR

#### CERTIFIED SHAREHOLDER REPORT OF REGISTERED

#### MANAGEMENT INVESTMENT COMPANIES
Investment Company Act File Number: 811-10093

T. Rowe Price QM U.S. Bond Index Fund, Inc.

(Exact name of registrant as specified in charter)

1307 Point Street, Baltimore, MD 21231

(Address of principal executive offices)

David Oestreicher

1307 Point Street, Baltimore, MD 21231

(Name and address of agent for service)

Registrant's telephone number, including area code: (410) 345-2000

Date of fiscal year end: October 31

Date of reporting period: April 30, 2025

------

#### Item 1. Reports to Shareholders

#### &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (a) Report pursuant to Rule 30e-1
![Image](g944258ifa2eeea050947ee86ef8.jpg)

#### Semi-Annual Shareholder Report

#### April 30, 2025

#### QM U.S. Bond Index Fund

#### Investor Class (PBDIX)
This semi-annual shareholder report contains important information about QM U.S. Bond Index Fund (the "fund") for the period of November 1, 2024 to April 30, 2025. You can find the fund's prospectus, financial information on Form N-CSR (which includes required tax information for dividends), holdings, proxy voting information, and other information at**www.troweprice.com/prospectus**. You can also request this information without charge by contacting T. Rowe Price at 1-800-638-5660 or info@troweprice.com or contacting your intermediary.

# **What were the fund costs for the last six months?** (based on a hypothetical $10,000 investment)

---

| | | |
|:---|:---|:---|
| | **Costs of a $10,000 investment** | **Costs paid as a percentage of a $10,000 investment** |
| QM U.S. Bond Index Fund - Investor Class | $13 | 0.25% |

---

#### What are some fund statistics?

# Fund Statistics

---

| | |
|:---|:---|
| Total Net Assets (000s) | $1779251 |
| Number of Portfolio Holdings | 1291 |

---

---

| | |
|:---|:---|
| Portfolio Turnover Rate | 34.7% |

---

# **What did the fund invest in?** 

# **Security Allocation** (as a % of Net Assets)

---

| | |
|:---|:---|
| U.S. Government Agency Obligations (Excluding Mortgage-Backed) | 37.7% |
| U.S. Government & Agency Mortgage-Backed Securities | 26.4 |
| Corporate Bonds | 23.3 |
| Asset-Backed Securities | 3.6 |
| Non-U.S. Government Mortgage-Backed Securities | 2.5 |
| Municipal Securities | 2.1 |
| Foreign Government Obligations & Municipalities | 1.6 |
| Securities Lending Collateral | 0.3 |
| Short-Term and Other | 2.5 |

---

# **Top Ten Holdings** (as a % of Net Assets)

---

| | |
|:---|:---|
| U.S. Treasury Notes | 27.3% |
| Federal National Mortgage Assn. | 12.4 |
| U.S. Treasury Bonds | 10.4 |
| Federal Home Loan Mortgage | 5.9 |
| Government National Mortgage Assn. | 5.7 |
| Federal Home Loan Mortgage Multifamily Structured PTC | 1.3 |
| UMBS | 1.3 |
| JPMorgan Chase | 0.6 |
| Bank of America | 0.5 |
| Santander Drive Auto Receivables Trust | 0.5 |

---

If you invest directly with T. Rowe Price, you can elect to receive future shareholder reports or other important documents through electronic delivery by enrolling at www.troweprice.com/paperless. If you invest through a financial intermediary such as an investment advisor, a bank, retirement plan sponsor or a brokerage firm, please contact that organization and ask if it can provide electronic delivery.

Visit www.troweprice.com/en/us/market-data-disclosures for additional legal notices & disclaimers.

202505-4461501

F134-053 6/25

QM U.S. Bond Index Fund

Investor Class (PBDIX)

T. Rowe Price Investment Services, Inc.

1307 Point Street

Baltimore, Maryland 21231

![Image](g944258ie96d9fe46d8f3c9553d4.jpg)

![Image](g944258ifa2eeea050947ee86ef8.jpg)

#### Semi-Annual Shareholder Report

#### April 30, 2025

#### QM U.S. Bond Index Fund

#### I Class (TSBLX)
This semi-annual shareholder report contains important information about QM U.S. Bond Index Fund (the "fund") for the period of November 1, 2024 to April 30, 2025. You can find the fund's prospectus, financial information on Form N-CSR (which includes required tax information for dividends), holdings, proxy voting information, and other information at**www.troweprice.com/prospectus**. You can also request this information without charge by contacting T. Rowe Price at 1-800-638-5660 or info@troweprice.com or contacting your intermediary.

# **What were the fund costs for the last six months?** (based on a hypothetical $10,000 investment)

---

| | | |
|:---|:---|:---|
| | **Costs of a $10,000 investment** | **Costs paid as a percentage of a $10,000 investment** |
| QM U.S. Bond Index Fund - I Class | $6 | 0.12% |

---

#### What are some fund statistics?

# Fund Statistics

---

| | |
|:---|:---|
| Total Net Assets (000s) | $1779251 |
| Number of Portfolio Holdings | 1291 |

---

---

| | |
|:---|:---|
| Portfolio Turnover Rate | 34.7% |

---

# **What did the fund invest in?** 

# **Security Allocation** (as a % of Net Assets)

---

| | |
|:---|:---|
| U.S. Government Agency Obligations (Excluding Mortgage-Backed) | 37.7% |
| U.S. Government & Agency Mortgage-Backed Securities | 26.4 |
| Corporate Bonds | 23.3 |
| Asset-Backed Securities | 3.6 |
| Non-U.S. Government Mortgage-Backed Securities | 2.5 |
| Municipal Securities | 2.1 |
| Foreign Government Obligations & Municipalities | 1.6 |
| Securities Lending Collateral | 0.3 |
| Short-Term and Other | 2.5 |

---

# **Top Ten Holdings** (as a % of Net Assets)

---

| | |
|:---|:---|
| U.S. Treasury Notes | 27.3% |
| Federal National Mortgage Assn. | 12.4 |
| U.S. Treasury Bonds | 10.4 |
| Federal Home Loan Mortgage | 5.9 |
| Government National Mortgage Assn. | 5.7 |
| Federal Home Loan Mortgage Multifamily Structured PTC | 1.3 |
| UMBS | 1.3 |
| JPMorgan Chase | 0.6 |
| Bank of America | 0.5 |
| Santander Drive Auto Receivables Trust | 0.5 |

---

If you invest directly with T. Rowe Price, you can elect to receive future shareholder reports or other important documents through electronic delivery by enrolling at www.troweprice.com/paperless. If you invest through a financial intermediary such as an investment advisor, a bank, retirement plan sponsor or a brokerage firm, please contact that organization and ask if it can provide electronic delivery.

Visit www.troweprice.com/en/us/market-data-disclosures for additional legal notices & disclaimers.

202505-4461501

F1364-053 6/25

QM U.S. Bond Index Fund

I Class (TSBLX)

T. Rowe Price Investment Services, Inc.

1307 Point Street

Baltimore, Maryland 21231

![Image](g944258ie96d9fe46d8f3c9553d4.jpg)

![Image](g944258ifa2eeea050947ee86ef8.jpg)

#### Semi-Annual Shareholder Report

#### April 30, 2025

#### QM U.S. Bond Index Fund

#### Z Class (TSBZX)
This semi-annual shareholder report contains important information about QM U.S. Bond Index Fund (the "fund") for the period of November 1, 2024 to April 30, 2025. You can find the fund's prospectus, financial information on Form N-CSR (which includes required tax information for dividends), holdings, proxy voting information, and other information at**www.troweprice.com/prospectus**. You can also request this information without charge by contacting T. Rowe Price at 1-800-638-5660 or info@troweprice.com or contacting your intermediary.

# **What were the fund costs for the last six months?** (based on a hypothetical $10,000 investment)

---

| | | |
|:---|:---|:---|
| | **Costs of a $10,000 investment** | **Costs paid as a percentage of a $10,000 investment** |
| QM U.S. Bond Index Fund - Z Class | $0 | 0.00% |

---

#### What are some fund statistics?

# Fund Statistics

---

| | |
|:---|:---|
| Total Net Assets (000s) | $1779251 |
| Number of Portfolio Holdings | 1291 |

---

---

| | |
|:---|:---|
| Portfolio Turnover Rate | 34.7% |

---

# **What did the fund invest in?** 

# **Security Allocation** (as a % of Net Assets)

---

| | |
|:---|:---|
| U.S. Government Agency Obligations (Excluding Mortgage-Backed) | 37.7% |
| U.S. Government & Agency Mortgage-Backed Securities | 26.4 |
| Corporate Bonds | 23.3 |
| Asset-Backed Securities | 3.6 |
| Non-U.S. Government Mortgage-Backed Securities | 2.5 |
| Municipal Securities | 2.1 |
| Foreign Government Obligations & Municipalities | 1.6 |
| Securities Lending Collateral | 0.3 |
| Short-Term and Other | 2.5 |

---

# **Top Ten Holdings** (as a % of Net Assets)

---

| | |
|:---|:---|
| U.S. Treasury Notes | 27.3% |
| Federal National Mortgage Assn. | 12.4 |
| U.S. Treasury Bonds | 10.4 |
| Federal Home Loan Mortgage | 5.9 |
| Government National Mortgage Assn. | 5.7 |
| Federal Home Loan Mortgage Multifamily Structured PTC | 1.3 |
| UMBS | 1.3 |
| JPMorgan Chase | 0.6 |
| Bank of America | 0.5 |
| Santander Drive Auto Receivables Trust | 0.5 |

---

If you invest directly with T. Rowe Price, you can elect to receive future shareholder reports or other important documents through electronic delivery by enrolling at www.troweprice.com/paperless. If you invest through a financial intermediary such as an investment advisor, a bank, retirement plan sponsor or a brokerage firm, please contact that organization and ask if it can provide electronic delivery.

Visit www.troweprice.com/en/us/market-data-disclosures for additional legal notices & disclaimers.

202505-4461501

F1365-053 6/25

QM U.S. Bond Index Fund

Z Class (TSBZX)

T. Rowe Price Investment Services, Inc.

1307 Point Street

Baltimore, Maryland 21231

![Image](g944258ie96d9fe46d8f3c9553d4.jpg)

------

#### Item 1. (b) Notice pursuant to Rule 30e-3.
Not applicable.

#### Item 2. Code of Ethics.
A code of ethics, as defined in Item 2 of Form N-CSR, applicable to its principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions is filed as an exhibit to the registrant's annual Form N-CSR. No substantive amendments were approved or waivers were granted to this code of ethics during the registrant's most recent fiscal half-year.

#### Item 3. Audit Committee Financial Expert.
Disclosure required in registrant's annual Form N-CSR.

#### Item 4. Principal Accountant Fees and Services.
Disclosure required in registrant's annual Form N-CSR.

#### Item 5. Audit Committee of Listed Registrants.
Not applicable.

#### Item 6. Investments.
(a) Not applicable. The complete schedule of investments is included in Item 7 of this Form N-CSR.

(b) Not applicable.

#### Item 7. Financial Statements and Financial Highlights for Open-End Management Investment Companies.
(a – b) Report pursuant to Regulation S-X.

------

Financial

Highlights

Portfolio

of

Investments

Financial

Statements

and

Notes

Additional

Fund

Information

April

30,

2025

#### Financial

#### Statements

#### and

#### Other

#### Information
For

more

insights

from

T. Rowe

Price

investment

professionals,

go

to

#### troweprice.com
.

T. ROWE

PRICE

PBDIX

QM

U.S.

Bond

Index

Fund

TSBLX

QM

U.S.

Bond

Index

Fund–

.

I Class

TSBZX

QM

U.S.

Bond

Index

Fund–

.

Z Class

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

(Unaudited)

#### Financial

#### Highlights

For

a

share

outstanding

throughout

each

period

#### Investor

#### Class

Months

.

Ended

4/30/25

..

Year

..

..

Ended

.

10/31/24

10/31/23

10/31/22

10/31/21

10/31/20

#### NET

#### ASSET

#### VALUE
Beginning

of

period

$

9.60 $

9.03 $

9.33 $

11.40 $

11.77 $

11.34 Investment

activities

Net

investment

income

(1)(2)

0.20 0.38 0.33 0.24 0.21 0.27 Net

realized

and

unrealized

gain/

loss

0.04 0.57 (0.30)

(2.07)

(0.22)

0.46 Total

from

investment

activities

0.24 0.95 0.03 (1.83)

(0.01)

0.73 Distributions

Net

investment

income

(0.20)

(0.38)

(0.33)

(0.24)

(0.21)

(0.28)

Net

realized

gain

—

—

—

—

(0.15)

(0.02)

Total

distributions

(0.20)

(0.38)

(0.33)

(0.24)

(0.36)

(0.30)

#### NET

#### ASSET

#### VALUE

#### End

#### of

#### period

#### $

#### 9.64

#### $

#### 9.60

#### $

#### 9.03

#### $

#### 9.33

#### $

#### 11.40

#### $

#### 11.77
T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

(Unaudited)

#### Financial

#### Highlights

For

a

share

outstanding

throughout

each

period

The

accompanying

notes

are

an

integral

part

of

these

financial

statements.

#### Investor

#### Class

Months

.

Ended

4/30/25

..

Year

..

..

Ended

.

10/31/24

10/31/23

10/31/22

10/31/21

10/31/20

#### Ratios/Supplemental

#### Data

#### Total

#### return

#### (2)(3)

#### 2.54%

#### 10.63%

#### 0.21%

#### (16.20)%

#### (0.08)%

#### 6.49%
Ratios

to

average

net

assets:

(2) Gross

expenses

before

waivers/

payments

by

Price

Associates

0.28%

(4) 0.29%

0.27%

0.27%

0.23%

0.29%

Net

expenses

after

waivers/

payments

by

Price

Associates

0.25%

(4) 0.25%

0.25%

0.25%

0.23%

0.29%

Net

investment

income

4.18%

(4) 3.96%

3.48%

2.23%

1.82%

2.36%

Portfolio

turnover

rate

(5) 34.7%

78.1%

73.9%

203.5%

225.2%

161.2%

Portfolio

turnover

rate,

excluding

mortgage

dollar

roll

transactions

19.8%

44.8%

39.3%

64.9%

63.7%

69.8%

Net

assets,

end

of

period

(in

millions)

$583

$597

$574

$551

$1,310

$1,620

0%

0%

0%

0%

0%

0%

(1) Per

share

amounts

calculated

using

average

shares

outstanding

method.

(2) Includes

the

impact

of

expense-related

arrangements

with

Price

Associates.

(3) Total

return

reflects

the

rate

that

an

investor

would

have

earned

on

an

investment

in

the

fund

during

each

period,

assuming

reinvestment

of

all

distributions,

and

payment

of

no

redemption

or

account

fees,

if

applicable.

Total

return

is

not

annualized

for

periods

less

than

one

year.

(4) Annualized

(5) The

portfolio

turnover

rate

calculation

includes

purchases

and

sales

from

the

mortgage

dollar

roll

transactions.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

(Unaudited)

#### Financial

#### Highlights

For

a

share

outstanding

throughout

each

period

#### I

#### Class
(1) 6

Months

.

Ended

4/30/25

..

Year

..

..

Ended

.

10/5/20

(1) Through

10/31/20

10/31/24

10/31/23

10/31/22

10/31/21

#### NET

#### ASSET

#### VALUE
Beginning

of

period

$

9.61 $

9.03 $

9.33 $

11.41 $

11.77 $

11.80 Investment

activities

Net

investment

income

(2)(3)

0.20 0.39 0.35 0.27 0.22 0.02 Net

realized

and

unrealized

gain/

loss

0.05 0.58 (0.30)

(2.09)

(0.20)

(0.03)

(4) Total

from

investment

activities

0.25 0.97 0.05 (1.82)

0.02 (0.01)

Distributions

Net

investment

income

(0.21)

(0.39)

(0.35)

(0.26)

(0.23)

(0.02)

Net

realized

gain

—

—

—

—

(0.15)

—

Total

distributions

(0.21)

(0.39)

(0.35)

(0.26)

(0.38)

(0.02)

#### NET

#### ASSET

#### VALUE

#### End

#### of

#### period

#### $

#### 9.65

#### $

#### 9.61

#### $

#### 9.03

#### $

#### 9.33

#### $

#### 11.41

#### $

#### 11.77
T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

(Unaudited)

#### Financial

#### Highlights

For

a

share

outstanding

throughout

each

period

The

accompanying

notes

are

an

integral

part

of

these

financial

statements.

#### I

#### Class
(1) 6

Months

.

Ended

4/30/25

..

Year

..

..

Ended

.

10/5/20

(1) Through

10/31/20

10/31/24

10/31/23

10/31/22

10/31/21

#### Ratios/Supplemental

#### Data

#### Total

#### return

#### (3)(5)

#### 2.60%

#### 10.89%

#### 0.34%

#### (16.16)%

#### 0.12%

#### (0.10)%
Ratios

to

average

net

assets:

(3) Gross

expenses

before

waivers/

payments

by

Price

Associates

0.13%

(6) 0.13%

0.13%

0.13%

0.13%

0.11%

(6) Net

expenses

after

waivers/

payments

by

Price

Associates

0.12%

(6) 0.12%

0.12%

0.12%

0.12%

0.11%

(6) Net

investment

income

4.31%

(6) 4.10%

3.61%

2.58%

1.94%

2.38%

(6) Portfolio

turnover

rate

(7) 34.7%

78.1%

73.9%

203.5%

225.2%

161.2%

Portfolio

turnover

rate,

excluding

mortgage

dollar

roll

transactions

19.8%

44.8%

39.3%

64.9%

63.7%

69.8%

Net

assets,

end

of

period

(in

millions)

$847

$787

$515

$510

$275

$25

0%

0%

0%

0%

0%

0%

(1) Inception

date

(2) Per

share

amounts

calculated

using

average

shares

outstanding

method.

(3) Includes

the

impact

of

expense-related

arrangements

with

Price

Associates.

(4) The

amount

presented

is

inconsistent

with

the

fund's

aggregate

gains

and

losses

because

of

the

timing

of

sales

and

redemptions

of

fund

shares

in

relation

to

fluctuating

market

values

for

the

investment

portfolio.

(5) Total

return

reflects

the

rate

that

an

investor

would

have

earned

on

an

investment

in

the

fund

during

each

period,

assuming

reinvestment

of

all

distributions,

and

payment

of

no

redemption

or

account

fees,

if

applicable.

Total

return

is

not

annualized

for

periods

less

than

one

year.

(6) Annualized

(7) The

portfolio

turnover

rate

calculation

includes

purchases

and

sales

from

the

mortgage

dollar

roll

transactions.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

(Unaudited)

#### Financial

#### Highlights

For

a

share

outstanding

throughout

each

period

#### Z

#### Class
(1) 6

Months

.

Ended

4/30/25

..

Year

..

..

Ended

.

10/5/20

(1) Through

10/31/20

10/31/24

10/31/23

10/31/22

10/31/21

#### NET

#### ASSET

#### VALUE
Beginning

of

period

$

9.60 $

9.03 $

9.33 $

11.40 $

11.77 $

11.80 Investment

activities

Net

investment

income

(2)(3)

0.21 0.41 0.36 0.29 0.24 0.02 Net

realized

and

unrealized

gain/

loss

0.04 0.57 (0.30)

(2.09)

(0.22)

(0.03)

(4) Total

from

investment

activities

0.25 0.98 0.06 (1.80)

0.02 (0.01)

Distributions

Net

investment

income

(0.21)

(0.41)

(0.36)

(0.27)

(0.24)

(0.02)

Net

realized

gain

—

—

—

—

(0.15)

—

Total

distributions

(0.21)

(0.41)

(0.36)

(0.27)

(0.39)

(0.02)

#### NET

#### ASSET

#### VALUE

#### End

#### of

#### period

#### $

#### 9.64

#### $

#### 9.60

#### $

#### 9.03

#### $

#### 9.33

#### $

#### 11.40

#### $

#### 11.77
T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

(Unaudited)

#### Financial

#### Highlights

For

a

share

outstanding

throughout

each

period

The

accompanying

notes

are

an

integral

part

of

these

financial

statements.

#### Z

#### Class
(1) 6

Months

.

Ended

4/30/25

..

Year

..

..

Ended

.

10/5/20

(1) Through

10/31/20

10/31/24

10/31/23

10/31/22

10/31/21

#### Ratios/Supplemental

#### Data

#### Total

#### return

#### (3)(5)

#### 2.66%

#### 10.90%

#### 0.46%

#### (15.99)%

#### 0.15%

#### (0.09)%
Ratios

to

average

net

assets:

(3) Gross

expenses

before

waivers/

payments

by

Price

Associates

0.10%

(6) 0.10%

0.10%

0.10%

0.12%

0.25%

(6) Net

expenses

after

waivers/

payments

by

Price

Associates

0.00%

(6) 0.00%

0.00%

0.00%

0.00%

0.00%

(6) Net

investment

income

4.44%

(6) 4.24%

3.80%

2.82%

2.07%

2.10%

(6) Portfolio

turnover

rate

(7) 34.7%

78.1%

73.9%

203.5%

225.2%

161.2%

Portfolio

turnover

rate,

excluding

mortgage

dollar

roll

transactions

19.8%

44.8%

39.3%

64.9%

63.7%

69.8%

Net

assets,

end

of

period

(in

thousands)

$348,962

$205,530

$79,290

$24,909

$1,879

$100

0%

0%

0%

0%

0%

0%

(1) Inception

date

(2) Per

share

amounts

calculated

using

average

shares

outstanding

method.

(3) Includes

the

impact

of

expense-related

arrangements

with

Price

Associates.

(4) The

amount

presented

is

inconsistent

with

the

fund's

aggregate

gains

and

losses

because

of

the

timing

of

sales

and

redemptions

of

fund

shares

in

relation

to

fluctuating

market

values

for

the

investment

portfolio.

(5) Total

return

reflects

the

rate

that

an

investor

would

have

earned

on

an

investment

in

the

fund

during

each

period,

assuming

reinvestment

of

all

distributions,

and

payment

of

no

redemption

or

account

fees,

if

applicable.

Total

return

is

not

annualized

for

periods

less

than

one

year.

(6) Annualized

(7) The

portfolio

turnover

rate

calculation

includes

purchases

and

sales

from

the

mortgage

dollar

roll

transactions.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

April

30,

2025

(Unaudited)

#### Portfolio

#### of

#### Investments

#### ‡

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

‡

#### ASSET-BACKED

#### SECURITIES

#### 3.6%

#### Car

#### Loan

#### 1.2%
Ally

Bank

Auto

Credit-Linked

Notes

Series

2024-B,

Class

B

5.117%,

9/15/32 (1)

Avis

Budget

Rental

Car

Funding

AESOP

Series

2020-1A,

Class

B

2.68%,

8/20/26 (1)

Bayview

Opportunity

Master

Fund

VII

Series

2024-CAR1,

Class

A,

FRN

SOFR30A

+

1.10%,

5.454%,

12/26/31 (1)

CarMax

Auto

Owner

Trust

Series

2023-3,

Class

B

5.47%,

2/15/29

Carvana

Auto

Receivables

Trust

Series

2021-P4,

Class

C

2.33%,

2/10/28

1,860

1,774

Carvana

Auto

Receivables

Trust

Series

2024-N1,

Class

B

5.63%,

5/10/30 (1)

635

643

Carvana

Auto

Receivables

Trust

Series

2024-P4,

Class

A3

4.64%,

1/10/30

Carvana

Auto

Receivables

Trust

Series

2024-P4,

Class

A4

4.74%,

12/10/30

620

627

Enterprise

Fleet

Financing

Series

2024-3,

Class

A3

4.98%,

8/21/28 (1)

Enterprise

Fleet

Financing

Series

2024-3,

Class

A4

5.06%,

3/20/31 (1)

Enterprise

Fleet

Financing

Series

2024-4,

Class

A2

4.69%,

7/20/27 (1)

530

531

Enterprise

Fleet

Financing

Series

2024-4,

Class

A4

4.70%,

6/20/31 (1)

790

797

Ford

Credit

Auto

Owner

Trust

Series

2020-2,

Class

C

1.74%,

4/15/33 (1)

2,020

1,987

Ford

Credit

Floorplan

Master

Owner

Trust

Series

2020-2,

Class

B

1.32%,

9/15/27

1,625

1,603

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

Huntington

Bank

Auto

Credit-Linked

Notes

Series

2024-1,

Class

B1

6.153%,

5/20/32 (1)

Huntington

Bank

Auto

Credit-Linked

Notes

Series

2025-1,

Class

B

4.957%,

3/21/33 (1)

1,376

1,374

Navistar

Financial

Dealer

Note

Master

Owner

Trust

Series

2024-1,

Class

A

5.59%,

4/25/29 (1)

640

645

Santander

Drive

Auto

Receivables

Trust

Series

2021-1,

Class

E

2.51%,

12/15/28

3,739

3,697

Santander

Drive

Auto

Receivables

Trust

Series

2021-3,

Class

E

2.70%,

10/16/28 (1)

4,300

4,257

SFS

Auto

Receivables

Securitization

Trust

Series

2024-2A,

Class

A3

5.33%,

11/20/29 (1)

850

860

SFS

Auto

Receivables

Securitization

Trust

Series

2024-2A,

Class

B

5.41%,

8/20/30 (1)

Toyota

Lease

Owner

Trust

Series

2025-A,

Class

A4

4.81%,

6/20/29 (1)

1,225

1,237

22,175

#### Other

#### Asset-Backed

#### Securities

#### 2.2%
ARES

LI

Series

2019-51A,

Class

A1R2,

CLO,

FRN

3M

TSFR

+

1.36%,

5.616%,

10/15/37 (1)

1,420

1,411

Auxilior

Term

Funding

Series

2024-1A,

Class

A2

5.84%,

3/15/27 (1)

Chenango

Park

Series

2018-1A,

Class

A2R,

CLO,

FRN

3M

TSFR

+

1.45%,

5.706%,

4/15/30 (1)

965

963

CIFC

Funding

Series

2018-1A,

Class

A1R,

CLO,

FRN

3M

TSFR

+

1.32%,

5.589%,

1/18/38 (1)

935

933

CyrusOne

Data

Centers

Issuer

I

Series

2024-2A,

Class

A2

4.50%,

5/20/49 (1)

2,490

2,408

Dell

Equipment

Finance

Trust

Series

2024-1,

Class

C

5.73%,

3/22/30 (1)

Dell

Equipment

Finance

Trust

Series

2024-2,

Class

A3

4.59%,

8/22/30 (1)

625

628

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

Driven

Brands

Funding

Series

2020-1A,

Class

A2

3.786%,

7/20/50 (1)

744

720

Driven

Brands

Funding

Series

2021-1A,

Class

A2

2.791%,

10/20/51 (1)

1,605

1,494

Elara

HGV

Timeshare

Issuer

Series

2023-A,

Class

A

6.16%,

2/25/38 (1)

Elara

HGV

Timeshare

Issuer

Series

2023-A,

Class

B

6.53%,

2/25/38 (1)

Elmwood

Series

2022-7A,

Class

AR,

CLO,

FRN

3M

TSFR

+

1.50%,

5.78%,

1/17/37 (1)

1,160

1,160

Halseypoint

Series

2022-6A,

Class

A1R,

CLO,

FRN

3M

TSFR

+

1.35%,

5.619%,

1/20/38 (1)

1,710

1,700

Hardee's

Funding

Series

2024-1A,

Class

A2

7.253%,

3/20/54 (1)

1,189

1,227

Highbridge

Loan

Management

Series

5A-2015,

Class

A1R3,

CLO,

FRN

3M

TSFR

+

1.06%,

5.316%,

10/15/30 (1)

Invesco

U.S.

Series

2023-1A,

Class

AR,

CLO,

FRN

3M

TSFR

+

1.57%,

5.842%,

4/22/37 (1)

730

730

Jamestown

XV

Series

2020-15A,

Class

A1R,

CLO,

FRN

3M

TSFR

+

1.37%,

5.626%,

7/15/35 (1)

1,315

1,312

Jersey

Mike's

Funding

Series

2021-1A,

Class

A2I

2.891%,

2/15/52 (1)

KKR

Series

2022-43A,

Class

A1R,

CLO,

FRN

3M

TSFR

+

1.75%,

6.006%,

1/15/36 (1)

1,080

1,081

Madison

Park

Funding

XXXIII

Series

2019-33A,

Class

AR,

CLO,

FRN

3M

TSFR

+

1.29%,

5.546%,

10/15/32 (1)

1,254

1,251

MVW

Series

2019-2A,

Class

A

2.22%,

10/20/38 (1)

MVW

Series

2020-1A,

Class

A

1.74%,

10/20/37 (1)

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

NMEF

Funding

Series

2025-A,

Class

A2

4.72%,

7/15/32 (1)

1,245

1,246

OCP

Series

2017-13A,

Class

AR2,

CLO,

FRN

3M

TSFR

+

1.34%,

5.609%,

11/26/37 (1)

2,370

2,364

Octane

Receivables

Trust

Series

2023-1A,

Class

A

5.87%,

5/21/29 (1)

Octane

Receivables

Trust

Series

2024-1A,

Class

A2

5.68%,

5/20/30 (1)

Octane

Receivables

Trust

Series

2024-RVM1,

Class

A

5.01%,

1/22/46 (1)

962

971

PEAC

Solutions

Receivables

Series

2025-1A,

Class

A2

4.94%,

10/20/28 (1)

2,435

2,439

Post

Road

Equipment

Finance

Series

2024-1A,

Class

A2

5.59%,

11/15/29 (1)

Post

Road

Equipment

Finance

Series

2025-1A,

Class

A2

4.90%,

5/15/31 (1)

1,665

1,672

Progress

Residential

Trust

Series

2021-SFR5,

Class

A

1.427%,

7/17/38 (1)

Progress

Residential

Trust

Series

2024-SFR5,

Class

A

3.00%,

8/9/29 (1)

745

697

SCF

Equipment

Leasing

Series

2024-1A,

Class

C

5.82%,

9/20/32 (1)

840

861

SCF

Equipment

Trust

Series

2025-1A,

Class

A2

4.82%,

7/22/30 (1)

1,285

1,287

SCF

Equipment

Trust

Series

2025-1A,

Class

A3

5.11%,

11/21/33 (1)

1,250

1,272

SEB

Funding

Series

2024-1A,

Class

A2

7.386%,

4/30/54 (1)

763

782

Signal

Peak

Series

2018-5A,

Class

A1R,

CLO,

FRN

3M

TSFR

+

1.55%,

5.832%,

4/25/37 (1)

2,310

2,309

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

TPIC

SPV

I

Series

2024-1A,

Class

A

7.131%,

11/30/44,

Acquisition

Date:

12/10/24,

Cost $2,009 (2)(3)(4)

2,009

2,009

Tricon

Residential

Trust

Series

2024-SFR3,

Class

A

4.50%,

8/17/41 (1)

1,063

1,052

Verdant

Receivables

Series

2024-1A,

Class

A2

5.68%,

12/12/31 (1)

39,047

#### Student

#### Loan

#### 0.2%
Navient

Private

Education

Refi

Loan

Trust

Series

2019-CA,

Class

A2

3.13%,

2/15/68 (1)

Navient

Private

Education

Refi

Loan

Trust

Series

2020-A,

Class

A2A

2.46%,

11/15/68 (1)

552

532

Navient

Private

Education

Refi

Loan

Trust

Series

2020-GA,

Class

A

1.17%,

9/16/69 (1)

Navient

Private

Education

Refi

Loan

Trust

Series

2020-HA,

Class

A

1.31%,

1/15/69 (1)

SMB

Private

Education

Loan

Trust

Series

2018-B,

Class

A2A

3.60%,

1/15/37 (1)

SMB

Private

Education

Loan

Trust

Series

2020-A,

Class

A2A

2.23%,

9/15/37 (1)

SMB

Private

Education

Loan

Trust

Series

2020-B,

Class

A1A

1.29%,

7/15/53 (1)

766

722

SMB

Private

Education

Loan

Trust

Series

2021-A,

Class

APT1

1.07%,

1/15/53 (1)

1,593

1,432

3,715

#### Total

#### Asset-Backed

#### Securities

#### (Cost

#### $65,091)

#### 64,937

#### CORPORATE

#### BONDS

#### 23.3%

#### FINANCIAL

#### INSTITUTIONS

#### 9.2%

#### Banking

#### 5.3%
ABN

AMRO

Bank,

4.75%,

7/28/25 (1)

Ally

Financial,

2.20%,

11/2/28

1,505

1,362

American

Express,

4.90%,

2/13/26

3,385

3,392

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

Banco

Santander,

3.49%,

5/28/30

600

563

Bank

of

America,

3.50%,

4/19/26

600

595

Bank

of

America,

6.00%,

10/15/36

Bank

of

America,

7.75%,

5/14/38

Bank

of

America,

VR,

2.592%,

4/29/31 (5)

1,875

1,692

Bank

of

America,

VR,

2.676%,

6/19/41 (5)

1,575

1,114

Bank

of

America,

VR,

3.824%,

1/20/28 (5)

2,280

2,255

Bank

of

America,

VR,

4.244%,

4/24/38 (5)

Bank

of

America,

VR,

5.425%,

8/15/35 (5)

2,000

1,953

Bank

of

New

York

Mellon,

VR,

6.474%,

10/25/34 (5)

1,440

1,573

Banque

Federative

du

Credit

Mutuel

,

4.935%,

1/26/26 (1)

3,570

3,580

Barclays,

VR,

2.852%,

5/7/26 (5)

1,640

1,639

Barclays,

VR,

5.674%,

3/12/28 (5)

1,045

1,066

BNP

Paribas,

VR,

5.497%,

5/20/30 (1)(5)

2,750

2,798

Capital

One

Financial,

3.65%,

5/11/27

1,430

1,407

Capital

One

Financial,

VR,

2.359%,

7/29/32 (5)

3,700

3,041

Capital

One

Financial,

VR,

6.051%,

2/1/35 (5)

Citigroup,

5.875%,

1/30/42

Citigroup,

VR,

3.887%,

1/10/28 (5)

2,050

2,027

Citigroup,

VR,

4.075%,

4/23/29 (5)

1,920

1,896

Danske

Bank,

VR,

5.705%,

3/1/30 (1)(5)

Discover

Bank,

2.70%,

2/6/30

2,000

1,800

Fifth

Third

Bancorp,

VR,

6.339%,

7/27/29 (5)

Goldman

Sachs

Group,

3.80%,

3/15/30

1,270

1,224

Goldman

Sachs

Group,

4.25%,

10/21/25

825

823

Goldman

Sachs

Group,

6.75%,

10/1/37

HSBC

Bank

USA,

5.875%,

11/1/34

550

560

HSBC

Holdings,

VR,

2.013%,

9/22/28 (5)

3,345

3,140

HSBC

Holdings,

VR,

6.332%,

3/9/44 (5)

1,725

1,814

ING

Groep

,

VR,

5.55%,

3/19/35 (5)

1,655

1,674

ING

Groep

,

VR,

6.114%,

9/11/34 (5)

740

778

JPMorgan

Chase,

2.95%,

10/1/26

980

964

JPMorgan

Chase,

VR,

2.956%,

5/13/31 (5)

1,230

1,122

JPMorgan

Chase,

VR,

3.782%,

2/1/28 (5)

990

979

JPMorgan

Chase,

VR,

3.882%,

7/24/38 (5)

4,905

4,244

JPMorgan

Chase,

VR,

5.299%,

7/24/29 (5)

3,170

3,242

Morgan

Stanley,

3.125%,

7/27/26

2,000

1,970

Morgan

Stanley,

4.30%,

1/27/45

750

622

Morgan

Stanley,

6.25%,

8/9/26

Morgan

Stanley,

VR,

3.217%,

4/22/42 (5)

830

611

Morgan

Stanley,

VR,

5.656%,

4/18/30 (5)

2,975

3,072

PNC

Financial

Services

Group,

VR,

4.758%,

1/26/27 (5)

1,920

1,920

Santander

Holdings

USA,

VR,

6.342%,

5/31/35 (5)

1,925

1,961

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

Santander

Holdings

USA,

VR,

6.499%,

3/9/29 (5)

885

918

Skandinaviska

Enskilda

Banken

,

5.125%,

3/5/27 (1)

2,930

2,971

Societe

Generale

,

5.25%,

2/19/27 (1)

1,230

1,239

Societe

Generale

,

VR,

6.066%,

1/19/35 (1)(5)

1,305

1,326

Sumitomo

Mitsui

Financial

Group,

5.464%,

1/13/26

1,755

1,768

Toronto-Dominion

Bank,

1.15%,

6/12/25

1,725

1,718

Toronto-Dominion

Bank,

4.994%,

4/5/29

2,200

2,245

Truist

Financial,

1.95%,

6/5/30

1,470

1,282

U.S.

Bancorp,

VR,

5.384%,

1/23/30 (5)

665

680

UBS

Group,

VR,

1.364%,

1/30/27 (1)(5)

1,700

1,660

UBS

Group,

VR,

2.193%,

6/5/26 (1)(5)

1,405

1,405

Wells

Fargo,

VR,

2.393%,

6/2/28 (5)

2,415

2,316

Wells

Fargo,

VR,

5.574%,

7/25/29 (5)

1,250

1,284

Wells

Fargo,

VR,

5.707%,

4/22/28 (5)

1,895

1,935

Wells

Fargo,

VR,

6.303%,

10/23/29 (5)

1,380

1,454

Westpac

New

Zealand,

5.195%,

2/28/29 (1)

1,935

1,976

94,027

#### Brokerage

#### Asset

#### Managers

#### Exchanges

#### 0.4%
Intercontinental

Exchange,

1.85%,

9/15/32

1,735

1,421

Intercontinental

Exchange,

5.25%,

6/15/31

1,585

1,641

LPL

Holdings,

5.65%,

3/15/35

3,700

3,661

6,723

#### Finance

#### Companies

#### 0.2%
AerCap

Ireland

Capital,

6.50%,

7/15/25

655

656

Avolon

Holdings

Funding,

6.375%,

5/4/28 (1)

1,560

1,607

GATX,

6.05%,

3/15/34

1,785

1,856

4,119

#### Insurance

#### 2.2%
Allstate,

6.125%,

12/15/32

American

International

Group,

3.875%,

1/15/35

Aon,

3.875%,

12/15/25

Aon

Corp.,

5.00%,

9/12/32

3,075

3,076

Arthur

J

Gallagher,

4.85%,

12/15/29

Athene

Global

Funding,

4.86%,

8/27/26 (1)

3,330

3,343

CNO

Global

Funding,

4.95%,

9/9/29 (1)

515

516

Corebridge

Global

Funding,

4.65%,

8/20/27 (1)

1,075

1,080

Elevance

Health,

4.55%,

3/1/48

1,135

937

Elevance

Health,

4.65%,

1/15/43

Fidelity

National

Financial,

4.50%,

8/15/28

1,615

1,594

Health

Care

Service,

5.45%,

6/15/34 (1)

1,095

1,101

Humana,

5.375%,

4/15/31

785

785

Humana,

5.95%,

3/15/34

835

854

Jackson

National

Life

Global

Funding,

4.90%,

1/13/27 (1)

3,620

3,643

Liberty

Mutual

Group,

4.50%,

6/15/49 (1)

1,670

1,236

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

Liberty

Mutual

Group,

4.85%,

8/1/44 (1)

1,370

1,179

MassMutual

Global

Funding

II,

5.10%,

4/9/27 (1)

2,940

2,993

New

York

Life

Insurance,

3.75%,

5/15/50 (1)

1,415

1,022

Principal

Financial

Group,

2.125%,

6/15/30

1,900

1,679

Principal

Financial

Group,

3.40%,

5/15/25

1,215

1,213

Principal

Financial

Group,

3.70%,

5/15/29

Principal

Financial

Group,

4.111%,

2/15/28 (1)

1,100

1,082

Protective

Life

Global

Funding,

1.17%,

7/15/25 (1)

2,345

2,327

RGA

Global

Funding,

5.448%,

5/24/29 (1)

1,730

1,783

Teachers

Insurance

&

Annuity

Association

of

America,

4.27%,

5/15/47 (1)

1,400

1,121

Travelers,

6.25%,

6/15/37

UnitedHealth

Group,

2.00%,

5/15/30

UnitedHealth

Group,

3.50%,

8/15/39

1,960

1,564

UnitedHealth

Group,

3.75%,

7/15/25

UnitedHealth

Group,

4.75%,

7/15/45

900

781

UnitedHealth

Group,

5.75%,

7/15/64

1,790

1,716

Willis

North

America,

4.50%,

9/15/28

1,110

1,108

40,207

#### Real

#### Estate

#### Investment

#### Trusts

#### 1.1%
Alexandria

Real

Estate

Equities,

3.95%,

1/15/27

Alexandria

Real

Estate

Equities,

4.00%,

2/1/50

1,975

1,434

Brixmor

Operating

Partnership,

3.90%,

3/15/27

Brixmor

Operating

Partnership,

4.05%,

7/1/30

760

730

Essex

Portfolio,

2.65%,

3/15/32

660

566

Essex

Portfolio,

4.50%,

3/15/48

1,455

1,226

Extra

Space

Storage,

4.00%,

6/15/29

Healthcare

Realty

Holdings,

3.625%,

1/15/28

605

584

Healthpeak

OP,

2.125%,

12/1/28

710

652

Healthpeak

OP,

2.875%,

1/15/31

Kilroy

Realty,

4.375%,

10/1/25

Prologis,

4.00%,

9/15/28

2,110

2,092

Public

Storage

Operating,

1.95%,

11/9/28

1,285

1,192

Realty

Income,

2.20%,

6/15/28

685

641

Realty

Income,

3.95%,

8/15/27

835

828

Realty

Income,

4.625%,

11/1/25

1,775

1,772

Regency

Centers,

3.60%,

2/1/27

Regency

Centers,

4.125%,

3/15/28

520

517

Regency

Centers,

4.40%,

2/1/47

2,000

1,646

Regency

Centers,

5.25%,

1/15/34

1,340

1,338

Simon

Property

Group,

3.80%,

7/15/50

2,830

2,081

18,867

Total

Financial

Institutions

163,943

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

#### INDUSTRIAL

#### 11.9%

#### Basic

#### Industry

#### 0.2%
Air

Products

&

Chemicals,

1.50%,

10/15/25

Celulosa

Arauco

y

Constitucion

,

3.875%,

11/2/27

570

554

Nutrien

,

4.00%,

12/15/26

525

523

Sherwin-Williams,

4.80%,

9/1/31

2,400

2,402

3,627

#### Capital

#### Goods

#### 1.3%
Amphenol,

4.75%,

3/30/26

Amphenol,

5.05%,

4/5/29

925

950

Boeing,

3.60%,

5/1/34

2,000

1,728

Boeing,

6.528%,

5/1/34

1,715

1,848

Caterpillar

Financial

Services,

5.00%,

5/14/27

4,225

4,304

CRH

America

Finance,

3.95%,

4/4/28 (1)

1,700

1,679

Ingersoll

Rand,

5.176%,

6/15/29

3,131

3,192

John

Deere

Capital,

4.40%,

9/8/31

2,530

2,521

John

Deere

Capital,

4.50%,

1/8/27

1,840

1,855

L3Harris

Technologies,

5.05%,

6/1/29

1,300

1,321

Lockheed

Martin,

4.07%,

12/15/42

Owens

Corning,

5.70%,

6/15/34

1,235

1,272

Regal

Rexnord,

6.40%,

4/15/33

1,640

1,673

22,805

#### Communications

#### 1.4%
America

Movil

,

6.375%,

3/1/35

AT&T,

4.35%,

3/1/29

1,020

1,018

AT&T,

5.40%,

2/15/34

2,415

2,458

Charter

Communications

Operating,

2.80%,

4/1/31

2,365

2,046

Charter

Communications

Operating,

3.70%,

4/1/51

1,795

1,103

Charter

Communications

Operating,

4.908%,

7/23/25

Charter

Communications

Operating,

6.10%,

6/1/29

690

713

Comcast,

2.65%,

2/1/30

Comcast,

3.20%,

7/15/36

Comcast,

3.95%,

10/15/25

845

842

Crown

Castle,

2.25%,

1/15/31

1,665

1,441

Crown

Castle,

3.70%,

6/15/26

700

691

Crown

Castle

Towers,

3.663%,

5/15/25 (1)

Meta

Platforms,

5.60%,

5/15/53

1,825

1,801

Omnicom

Group,

3.60%,

4/15/26

695

688

Rogers

Communications,

3.625%,

12/15/25

Rogers

Communications,

5.30%,

2/15/34

1,885

1,861

T-Mobile

USA,

3.75%,

4/15/27

3,565

3,521

Time

Warner

Cable,

6.55%,

5/1/37

Time

Warner

Cable,

6.75%,

6/15/39

2,580

2,573

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

Verizon

Communications,

1.68%,

10/30/30

625

536

Verizon

Communications,

4.00%,

3/22/50

1,500

1,127

Vodafone

Group,

4.25%,

9/17/50

700

527

Vodafone

Group,

4.875%,

6/19/49

Walt

Disney,

3.70%,

10/15/25

24,688

#### Consumer

#### Cyclical

#### 2.1%
Alibaba

Group

Holding,

4.00%,

12/6/37

2,300

1,988

American

Honda

Finance,

4.90%,

3/12/27

2,790

2,816

AutoZone,

1.65%,

1/15/31

2,000

1,685

AutoZone,

3.125%,

4/21/26

AutoZone,

3.75%,

6/1/27

AutoZone,

5.05%,

7/15/26

1,390

1,398

CBRE

Services,

5.50%,

4/1/29

580

595

Daimler

Truck

Finance

North

America,

5.375%,

1/18/34 (1)

560

555

Ford

Motor

Credit,

5.125%,

11/5/26

1,435

1,421

Ford

Motor

Credit,

7.122%,

11/7/33

635

638

General

Motors

Financial,

5.55%,

7/15/29

600

603

Home

Depot,

5.875%,

12/16/36

3,000

3,198

Hyundai

Capital

America,

1.30%,

1/8/26 (1)(6)

1,510

1,476

Hyundai

Capital

America,

5.35%,

3/19/29 (1)

500

503

Hyundai

Capital

America,

5.50%,

3/30/26 (1)

820

825

McDonald's,

1.45%,

9/1/25

935

923

McDonald's,

3.30%,

7/1/25

Mercedes-Benz

Finance

North

America,

4.80%,

3/30/26 (1)

1,930

1,938

O'Reilly

Automotive,

3.60%,

9/1/27

O'Reilly

Automotive,

3.90%,

6/1/29

2,470

2,404

O'Reilly

Automotive,

5.75%,

11/20/26

PACCAR

Financial,

5.00%,

5/13/27

3,070

3,127

PACCAR

Financial,

5.20%,

11/9/26

2,895

2,944

Ross

Stores,

1.875%,

4/15/31

TJX,

1.60%,

5/15/31

1,425

1,217

Toyota

Motor

Credit,

4.80%,

1/5/26

2,945

2,952

Uber

Technologies,

4.30%,

1/15/30

2,710

2,684

Volkswagen

Group

of

America

Finance,

4.95%,

8/15/29 (1)

37,525

#### Consumer

#### Non-Cyclical

#### 2.8%
AbbVie,

3.20%,

5/14/26

AbbVie,

4.45%,

5/14/46

1,280

1,086

AbbVie,

4.50%,

5/14/35

1,235

1,182

AbbVie,

4.70%,

5/14/45

1,385

1,225

AbbVie,

4.80%,

3/15/29

1,315

1,340

Altria

Group,

2.35%,

5/6/25

Amgen,

2.60%,

8/19/26

1,275

1,248

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

Amgen,

2.77%,

9/1/53

1,239

710

Amgen,

5.15%,

3/2/28

1,615

1,647

Anheuser-Busch

InBev

Worldwide,

5.45%,

1/23/39

Astrazeneca

Finance,

4.875%,

3/3/28

2,300

2,352

Banner

Health,

1.897%,

1/1/31

850

738

BAT

Capital,

4.39%,

8/15/37

3,395

2,975

BAT

Capital,

5.834%,

2/20/31

845

878

Becton

Dickinson

&

Company,

5.081%,

6/7/29

1,505

1,537

Bristol-Myers

Squibb,

4.25%,

10/26/49

1,055

840

Cardinal

Health,

3.75%,

9/15/25 (6)

905

901

Centra

Health,

4.70%,

1/1/48

CommonSpirit

Health,

2.782%,

10/1/30

980

886

CommonSpirit

Health,

3.91%,

10/1/50

Conopco

,

6.625%,

4/15/28

CVS

Health,

1.875%,

2/28/31

1,135

955

CVS

Health,

5.125%,

7/20/45

925

799

CVS

Health,

6.00%,

6/1/63

2,705

2,510

Hackensack

Meridian

Health,

4.211%,

7/1/48

1,680

1,374

HCA,

4.125%,

6/15/29

1,695

1,650

HCA,

5.45%,

9/15/34

890

879

Icon

Investments

Six,

5.849%,

5/8/29

Indiana

University

Health

Obligated

Group,

3.97%,

11/1/48

1,030

807

IQVIA,

6.25%,

2/1/29

735

757

JDE

Peet's

,

1.375%,

1/15/27 (1)

1,245

1,174

Keurig

Dr

Pepper,

2.55%,

9/15/26

Mars,

4.60%,

3/1/28 (1)

2,120

2,143

MedStar

Health,

Series

20A,

3.626%,

8/15/49

920

643

Memorial

Sloan-Kettering

Cancer

Center,

Series

2015,

4.20%,

7/1/55

600

Merck,

5.00%,

5/17/53

810

734

Mondelez

International,

4.75%,

2/20/29

3,800

3,863

Nestle

Holdings,

4.85%,

3/14/33 (1)(6)

2,700

2,724

Northwell

Healthcare,

3.979%,

11/1/46

1,275

954

Perrigo

Finance

Unlimited,

4.90%,

6/15/30

1,725

1,645

Revvity

,

1.90%,

9/15/28

1,575

1,445

Solventum

,

5.40%,

3/1/29

1,735

1,769

Stanford

Health

Care,

Series

2018,

3.795%,

11/15/48

West

Virginia

United

Health

System

Obligated

Group,

Series

2018,

4.924%,

6/1/48

1,620

1,401

49,884

#### Energy

#### 1.8%
Boardwalk

Pipelines,

3.40%,

2/15/31

2,130

1,943

BP

Capital

Markets

America,

3.41%,

2/11/26

1,280

1,269

Cameron

LNG,

2.902%,

7/15/31 (1)

520

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

Cameron

LNG,

3.701%,

1/15/39 (1)

Canadian

Natural

Resources,

2.95%,

7/15/30

1,520

1,380

Cheniere

Energy

Partners,

5.75%,

8/15/34

1,865

1,868

Diamondback

Energy,

5.15%,

1/30/30

550

558

Enbridge,

4.25%,

12/1/26

Enbridge,

5.50%,

12/1/46

555

519

Enbridge,

5.625%,

4/5/34

795

805

Enbridge,

6.70%,

11/15/53

610

644

Enbridge

Energy

Partners,

5.50%,

9/15/40

Energy

Transfer,

5.60%,

9/1/34

1,505

1,481

Eni,

5.50%,

5/15/34 (1)

845

837

Eni,

5.95%,

5/15/54 (1)

930

878

Enterprise

Products

Operating,

4.60%,

1/11/27

2,845

2,865

Kinder

Morgan,

5.20%,

6/1/33

1,800

1,770

Marathon

Petroleum,

5.15%,

3/1/30

1,955

1,968

MPLX,

5.65%,

3/1/53

1,600

1,421

Occidental

Petroleum,

5.375%,

1/1/32

1,430

1,362

ONEOK,

4.75%,

10/15/31

1,340

1,300

Pioneer

Natural

Resources,

1.125%,

1/15/26

695

679

Pioneer

Natural

Resources,

5.10%,

3/29/26

635

639

Sabine

Pass

Liquefaction,

4.20%,

3/15/28

815

810

Sabine

Pass

Liquefaction,

4.50%,

5/15/30

655

646

Spectra

Energy

Partners,

3.375%,

10/15/26

Transcontinental

Gas

Pipe

Line,

4.60%,

3/15/48

790

655

Williams,

4.85%,

3/1/48

Williams,

4.90%,

3/15/29

1,415

1,428

Woodside

Finance,

3.70%,

9/15/26 (1)

Woodside

Finance,

3.70%,

3/15/28 (1)

Woodside

Finance,

4.50%,

3/4/29 (1)

1,435

1,415

31,843

#### Industrial

#### Other

#### 0.1%
Georgetown

University,

Series

B,

4.315%,

4/1/49

1,475

1,211

President

&

Fellows

of

Harvard

College,

3.619%,

10/1/37

1,548

#### Technology

#### 1.4%
Apple,

3.20%,

5/13/25

Atlassian

,

5.25%,

5/15/29

760

771

Broadcom,

4.80%,

4/15/28

3,290

3,334

Cadence

Design

Systems,

4.30%,

9/10/29

1,090

1,089

Fiserv,

3.20%,

7/1/26

Fiserv,

5.45%,

3/15/34

2,125

2,135

Foundry

JV

Holdco,

5.90%,

1/25/33 (1)

765

779

Foundry

JV

Holdco,

6.15%,

1/25/32 (1)

885

918

Intel,

5.90%,

2/10/63

1,945

1,745

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

Micron

Technology,

4.185%,

2/15/27

805

804

Motorola

Solutions,

5.00%,

4/15/29

835

847

NXP,

3.15%,

5/1/27

Oracle,

5.375%,

7/15/40

2,925

2,758

RELX

Capital,

3.00%,

5/22/30

1,120

1,047

Roper

Technologies,

2.00%,

6/30/30

575

502

Roper

Technologies,

3.80%,

12/15/26

660

653

ServiceNow

,

1.40%,

9/1/30

3,710

3,182

TR

Finance,

3.35%,

5/15/26

VMware,

1.40%,

8/15/26

3,475

3,334

24,559

#### Transportation

#### 0.8%
American

Airlines

PTT,

Series

2019-1,

Class

AA,

3.15%,

2/15/32

Burlington

Northern

Santa

Fe,

6.15%,

5/1/37

Canadian

National

Railway,

5.85%,

11/1/33

920

973

Canadian

National

Railway,

6.25%,

8/1/34

Canadian

Pacific

Railway,

1.75%,

12/2/26

845

812

Canadian

Pacific

Railway,

2.875%,

11/15/29

1,140

1,067

Canadian

Pacific

Railway,

3.50%,

5/1/50

1,155

803

Canadian

Pacific

Railway,

4.70%,

5/1/48

720

620

ERAC

USA

Finance,

4.50%,

2/15/45 (1)

ERAC

USA

Finance,

4.90%,

5/1/33 (1)

1,595

1,567

FedEx,

4.40%,

1/15/47 (1)

6,500

4,945

Transurban

Finance,

2.45%,

3/16/31 (1)

1,820

1,597

Transurban

Finance,

3.375%,

3/22/27 (1)

Transurban

Finance,

4.125%,

2/2/26 (1)

United

Airlines

PTT,

Series

2016-2,

Class

A,

3.10%,

10/7/28

571

529

United

Airlines

PTT,

Series

2018-1,

Class

A,

3.70%,

3/1/30 (6)

840

771

14,554

Total

Industrial

211,033

#### UTILITY

#### 2.2%

#### Electric

#### 1.8%
Ameren,

5.70%,

12/1/26

1,820

1,851

American

Electric

Power,

5.20%,

1/15/29

2,595

2,652

Berkshire

Hathaway

Energy,

6.125%,

4/1/36

CenterPoint

Energy

Houston

Electric,

Series

K2,

6.95%,

3/15/33

CMS

Energy,

4.875%,

3/1/44

635

563

DTE

Energy,

5.10%,

3/1/29

2,645

2,683

DTE

Energy,

5.85%,

6/1/34

Duke

Energy,

2.65%,

9/1/26

Duke

Energy

Florida,

6.35%,

9/15/37

Duke

Energy

Progress,

5.35%,

3/15/53

600

573

Duke

Energy

Progress,

6.30%,

4/1/38

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

Exelon,

3.40%,

4/15/26

1,815

1,797

FirstEnergy

Pennsylvania

Electric,

4.30%,

1/15/29 (1)

2,320

2,286

FirstEnergy

Transmission,

5.00%,

1/15/35

610

600

Florida

Power

&

Light,

5.30%,

6/15/34

3,040

3,108

Georgia

Power,

4.95%,

5/17/33

895

890

Mid-Atlantic

Interstate

Transmission,

4.10%,

5/15/28 (1)

1,765

1,747

Nevada

Power,

Series

N,

6.65%,

4/1/36

New

York

State

Electric

&

Gas,

5.30%,

8/15/34 (1)

1,195

1,193

NextEra

Energy

Capital

Holdings,

5.749%,

9/1/25

1,355

1,360

Pacific

Gas

&

Electric,

2.10%,

8/1/27

1,985

1,869

PECO

Energy,

5.95%,

10/1/36

Public

Service

Electric

&

Gas,

5.70%,

12/1/36

San

Diego

Gas

&

Electric,

Series

FFF,

6.125%,

9/15/37

San

Diego

Gas

&

Electric,

Series

TTT,

4.10%,

6/15/49

1,790

1,375

Southern,

4.40%,

7/1/46

1,935

1,561

Southern,

5.70%,

3/15/34

725

748

Southern

California

Edison,

5.15%,

6/1/29

2,105

2,131

Southwestern

Public

Service,

6.00%,

6/1/54

Tampa

Electric,

6.15%,

5/15/37

700

734

32,387

#### Natural

#### Gas

#### 0.4%
APA

Infrastructure,

4.25%,

7/15/27 (1)

APA

Infrastructure,

5.125%,

9/16/34 (1)

Engie

,

5.625%,

4/10/34 (1)

660

667

NiSource,

1.70%,

2/15/31

1,280

1,080

NiSource,

3.49%,

5/15/27

710

698

NiSource,

3.95%,

3/30/48

1,000

759

NiSource,

5.35%,

4/1/34

1,850

1,866

Southern

California

Gas,

Series

KK,

5.75%,

11/15/35

Southern

Gas

Capital,

4.95%,

9/15/34

1,735

1,694

7,752

Total

Utility

40,139

#### Total

#### Corporate

#### Bonds

#### (Cost

#### $433,506)

#### 415,115

#### FOREIGN

#### GOVERNMENT

#### OBLIGATIONS

#### &

#### MUNICIPALITIES

#### 1.6%

#### Local

#### Authorities

#### 0.8%
Province

of

Alberta,

3.30%,

3/15/28

1,605

1,584

Province

of

Alberta

Canada,

4.50%,

1/24/34

1,405

1,400

Province

of

British

Columbia,

4.20%,

7/6/33

2,644

2,591

Province

of

Manitoba

Canada,

4.30%,

7/27/33

2,045

2,012

Province

of

New

Brunswick,

3.625%,

2/24/28

2,545

2,532

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

Province

of

Ontario,

3.70%,

9/17/29

4,360

4,319

Province

of

Quebec,

Series

PD,

7.50%,

9/15/29

14,556

#### Owned

#### No

#### Guarantee

#### 0.1%
Autoridad

del

Canal

de

Panama,

4.95%,

7/29/35 (1)

Corp

Nacional

del

Cobre

de

Chile,

3.75%,

1/15/31 (1)(6)

570

526

802

#### Sovereign

#### 0.7%
Government

of

Qatar,

3.75%,

4/16/30 (1)

730

715

Kingdom

of

Saudi

Arabia,

5.375%,

1/13/31 (1)

2,010

2,070

Republic

of

Chile,

5.65%,

1/13/37

3,740

3,833

Republic

of

Peru,

5.375%,

2/8/35

740

731

Republic

of

Poland,

3.25%,

4/6/26

890

881

United

Mexican

States,

2.659%,

5/24/31

5,154

4,391

12,621

#### Total

#### Foreign

#### Government

#### Obligations

#### &

#### Municipalities

#### (Cost

#### $28,697)

#### 27,979

#### MUNICIPAL

#### SECURITIES

#### 2.1%

#### California

#### 0.3%
Bay

Area

Toll

Auth.,

Series S-1,

Build

America,

6.918%,

4/1/40

Bay

Area

Toll

Auth.,

Toll

Bridge

Revenue

Bonds,

Series S-10,

3.176%,

4/1/41

1,275

988

California,

Build

America,

GO,

7.625%,

3/1/40

1,350

1,620

Inland

Valley

Dev.

Agency,

Tax

Allocation,

Series B,

5.50%,

3/1/33 (7)

Los

Angeles

Airport,

Series C,

Build

America,

7.053%,

5/15/40

700

805

Regents

of

the

Univ.

of

California

Medical

Center

Ed

Revenue

Bonds,

Series N,

3.256%,

5/15/60

700

San

Diego

County

Water

Auth.,

Series B,

Build

America,

6.138%,

5/1/49

San

Jose

Redev

.

Agency,

Senior

Tax

Allocation,

Series A-T,

3.375%,

8/1/34

610

553

5,324

#### Florida

#### 0.1%
Florida

Dev.

Finance,

Nova

Southeastern

Univ.,

Series B,

4.109%,

4/1/50

1,425

1,140

1,140

#### Georgia

#### 0.2%
Fulton

County,

Series 2010-B,

Build

America,

GO,

5.148%,

7/1/39

2,660

2,652

Municipal

Electric

Auth.

of

Georgia,

Build

America,

Vogtle

Units,

6.655%,

4/1/57

1,692

1,844

4,496

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

#### Illinois

#### 0.2%
Chicago

O'Hare

Int'l

Airport,

Series B,

Build

America,

6.395%,

1/1/40

1,350

1,455

Chicago

O'Hare

Int'l

Airport,

Senior

Lien,

Series D,

2.346%,

1/1/30

625

573

Illinois

Toll

Highway

Auth.,

Series A,

Build

America,

6.184%,

1/1/34

Metropolitan

Water

Reclamation

Dist.

of

Greater

Chicago,

Build

America,

GO,

5.72%,

12/1/38

2,858

#### Maryland

#### 0.1%
Maryland

Economic

Development,

Seagirt

Marine

Terminal,

Series B,

4.75%,

6/1/42

2,045

1,779

1,779

#### Michigan

#### 0.1%
Detroit

City

School

Dist.,

Qualified

School

Construction

Bonds,

GO,

6.645%,

5/1/29

1,255

1,366

1,366

#### Minnesota

#### 0.1%
Western

Minnesota

Municipal

Power

Agency,

Series A,

3.156%,

1/1/39

2,350

1,988

1,988

#### New

#### Jersey

#### 0.1%
New

Jersey

Turnpike

Auth.,

Series F,

Build

America,

7.414%,

1/1/40

1,000

1,206

1,206

#### New

#### York

#### 0.2%
Dormitory

Auth.

of

the

State

of

New

York,

New

York

Univ.,

Series B,

3.879%,

7/1/46

950

754

Dormitory

Auth.

of

the

State

of

New

York,

New

York

Univ.,

Series B,

4.85%,

7/1/48

800

724

Metropolitan

Transportation

Auth.,

Build

America,

6.548%,

11/15/31

1,315

1,391

Metropolitan

Transportation

Auth.,

Dedicated

Tax

Fund,

Build

America,

7.336%,

11/15/39

Port

Auth.

of

New

York

&

New

Jersey,

Series 182,

5.31%,

8/1/46

3,054

#### Ohio

#### 0.1%
American

Municipal

Power,

Series B,

Build

America,

6.449%,

2/15/44

2,005

2,121

2,121

#### Oregon

#### 0.1%
Oregon

DOT,

Senior

Lien,

Series B,

1.76%,

11/15/32

2,400

2,005

2,005

#### Pennsylvania

#### 0.0%
Philadelphia

Auth.

for

IDA,

3.964%,

4/15/26

#### Texas

#### 0.3%
Central

Texas

Turnpike

System,

Series C,

3.029%,

8/15/41

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

Dallas/Fort

Worth

Int'l

Airport,

Series A,

2.994%,

11/1/38

Dallas/Fort

Worth

Int'l

Airport,

Series C,

3.089%,

11/1/40

3,945

3,117

Grand

Parkway

Transportation,

Series B,

3.236%,

10/1/52

Texas

Natural

Gas

Securitization

Fin.,

Series 2023-1,

Class

A2,

5.169%,

4/1/41

705

711

Texas

Private

Activity

Bond

Surface

Transportation,

North

Tarrant

Express,

Series B,

3.922%,

12/31/49

2,400

1,881

5,762

#### Virginia

#### 0.0%
Virginia

Public

Building

Auth.,

Series B-2,

Build

America,

5.90%,

8/1/30

540

559

559

#### Wisconsin

#### 0.2%
Public

Finance

Auth.,

Bayhealth

Medical

Center,

Series B,

3.405%,

7/1/51

2,520

1,753

Wisconsin

General

Fund

Annual

Appropriation,

Series A,

3.954%,

5/1/36

1,700

1,571

3,324

#### Total

#### Municipal

#### Securities

#### (Cost

#### $42,447)

#### 37,156

#### NON-U.S.

#### GOVERNMENT

#### MORTGAGE-BACKED

#### SECURITIES

#### 2.5%

#### Collateralized

#### Mortgage

#### Obligations

#### 1.0%
Angel

Oak

Mortgage

Trust

Series

2020-6,

Class

A2,

CMO,

ARM,

1.518%,

5/25/65 (1)

Angel

Oak

Mortgage

Trust

Series

2021-1,

Class

A1,

CMO,

ARM,

0.909%,

1/25/66 (1)

902

769

Angel

Oak

Mortgage

Trust

Series

2021-2,

Class

A1,

CMO,

ARM,

0.985%,

4/25/66 (1)

797

689

Arroyo

Mortgage

Trust

Series

2019-2,

Class

A2,

CMO,

ARM,

3.498%,

4/25/49 (1)

Barclays

Mortgage

Loan

Trust

Series

2021-NQM1,

Class

A3,

CMO,

ARM,

2.189%,

9/25/51 (1)

810

731

Bayview

Financing

Trust

Series

2024-2F,

Class

A,

CMO,

ARM,

7.084%,

9/25/29,

Acquisition

Date:

8/29/24,

Cost $1,795 (2)(3)(4)

1,795

1,795

Citigroup

Mortgage

Loan

Trust

Series

2020-EXP2,

Class

A3,

CMO,

ARM,

2.50%,

8/25/50 (1)

965

832

COLT

Mortgage

Loan

Trust

Series

2020-3,

Class

A1,

CMO,

ARM,

1.506%,

4/27/65 (1)

Connecticut

Avenue

Securities

Trust

Series

2023-R04,

Class

1M1,

CMO,

ARM,

SOFR30A

+

2.30%,

6.653%,

5/25/43 (1)

1,804

1,837

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

EFMT

Series

2025-INV1,

Class

A1,

CMO,

STEP,

5.626%,

3/25/70 (1)

500

501

Ellington

Financial

Mortgage

Trust

Series

2019-2,

Class

A3,

CMO,

ARM,

3.046%,

11/25/59 (1)

Ellington

Financial

Mortgage

Trust

Series

2020-2,

Class

A1,

CMO,

ARM,

1.178%,

10/25/65 (1)

552

516

Galton

Funding

Mortgage

Trust

Series

2018-1,

Class

A23,

CMO,

ARM,

3.50%,

11/25/57 (1)

GS

Mortgage-Backed

Securities

Trust

Series

2020-INV1,

Class

A14,

CMO,

ARM,

2.912%,

10/25/50 (1)

952

810

JPMorgan

Mortgage

Trust

Series

2023-DSC2,

Class

A1,

CMO,

ARM,

5.25%,

11/25/63 (1)

538

536

MetLife

Securitization

Trust

Series

2018-1A,

Class

A,

CMO,

ARM,

3.75%,

3/25/57 (1)

613

594

NYMT

Loan

Trust

Series

2025-INV1,

Class

A1,

CMO,

STEP,

5.402%,

4/25/60 (1)

1,100

1,104

OBX

Trust

Series

2019-EXP3,

Class

1A9,

CMO,

ARM,

3.50%,

10/25/59 (1)

OBX

Trust

Series

2019-EXP3,

Class

2A2,

CMO,

ARM,

1M

TSFR

+

1.214%,

5.541%,

10/25/59 (1)

RCKT

Mortgage

Trust

Series

2024-CES9,

Class

A1A,

CMO,

STEP,

5.582%,

12/25/44 (1)

Sequoia

Mortgage

Trust

Series

2018-CH2,

Class

A3,

CMO,

ARM,

4.00%,

6/25/48 (1)

SG

Residential

Mortgage

Trust

Series

2019-3,

Class

A1,

CMO,

ARM,

2.703%,

9/25/59 (1)

Starwood

Mortgage

Residential

Trust

Series

2019-INV1,

Class

A3,

CMO,

ARM,

2.916%,

9/27/49 (1)

Starwood

Mortgage

Residential

Trust

Series

2020-INV1,

Class

A1,

CMO,

ARM,

1.027%,

11/25/55 (1)

Structured

Agency

Credit

Risk

Debt

Notes

Series

2021-DNA7,

Class

M1,

CMO,

ARM,

SOFR30A

+

0.85%,

5.204%,

11/25/41 (1)

656

654

Structured

Agency

Credit

Risk

Debt

Notes

Series

2025-HQA1,

Class

A1,

CMO,

ARM,

SOFR30A

+

0.95%,

5.304%,

2/25/45 (1)

981

976

Verus

Securitization

Trust

Series

2019-INV3,

Class

A1,

CMO,

ARM,

3.692%,

11/25/59 (1)

Verus

Securitization

Trust

Series

2020-1,

Class

A3,

CMO,

STEP,

3.724%,

1/25/60 (1)

831

815

Verus

Securitization

Trust

Series

2021-1,

Class

A1,

CMO,

ARM,

0.815%,

1/25/66 (1)

Verus

Securitization

Trust

Series

2023-INV1,

Class

A1,

CMO,

STEP,

5.999%,

2/25/68 (1)

1,293

1,293

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

Verus

Securitization

Trust

Series

2024-INV1,

Class

A2,

CMO,

STEP,

6.318%,

3/25/69 (1)

1,380

1,392

18,129

#### Commercial

#### Mortgage-Backed

#### Securities

#### 1.5%
BANK5

Series

2024-5YR12,

Class

A3,

ARM,

5.902%,

12/15/57

785

823

BBCMS

Mortgage

Trust

Series

2019-BWAY,

Class

D,

ARM,

1M

TSFR

+

2.274%,

6.596%,

11/15/34 (1)

545

BBCMS

Mortgage

Trust

Series

2024-5C27,

Class

A3,

6.014%,

7/15/57

Benchmark

Mortgage

Trust

Series

2024-V8,

Class

AM,

ARM,

6.859%,

7/15/57

3,465

3,674

BX

Commercial

Mortgage

Trust

Series

2024-SLCT,

Class

A,

ARM,

1M

TSFR

+

1.323%,

5.645%,

1/15/42 (1)

3,185

3,162

BX

Trust

Series

2025-ROIC,

Class

A,

ARM,

1M

TSFR

+

1.144%,

5.466%,

3/15/30 (1)

4,105

4,025

Citigroup

Commercial

Mortgage

Trust

Series

2015-GC33,

Class

A4,

3.778%,

9/10/58

Commercial

Mortgage

Trust

Series

2015-LC21,

Class

A4,

3.708%,

7/10/48

1,134

1,132

CONE

Trust

Series

2024-DFW1,

Class

A,

ARM,

1M

TSFR

+

1.642%,

5.964%,

8/15/41 (1)

685

682

Hudson

Yards

Mortgage

Trust

Series

2025-SPRL,

Class

A,

ARM,

5.649%,

1/13/40 (1)

1,720

1,768

JPMorgan

Chase

Commercial

Mortgage

Securities

Trust

Series

2020-609M,

Class

A,

ARM,

1M

TSFR

+

1.734%,

6.056%,

10/15/33 (1)

1,625

1,623

MHC

Commercial

Mortgage

Trust

Series

2021-MHC,

Class

B,

ARM,

1M

TSFR

+

1.215%,

5.537%,

4/15/38 (1)

3,180

3,172

Morgan

Stanley

Bank

of

America

Merrill

Lynch

Trust

Series

2015-C24,

Class

AS,

ARM,

4.036%,

5/15/48

700

688

Morgan

Stanley

Bank

of

America

Merrill

Lynch

Trust

Series

2015-C27,

Class

AS,

4.068%,

12/15/47

1,390

1,376

Morgan

Stanley

Capital

I

Trust

Series

2014-150E,

Class

A,

3.912%,

9/9/32 (1)

2,780

2,466

TX

Trust

Series

2024-HOU,

Class

A,

ARM,

1M

TSFR

+

1.591%,

5.913%,

6/15/39 (1)

660

653

WB

Commercial

Mortgage

Trust

Series

2024-HQ,

Class

A,

ARM,

6.134%,

3/15/40 (1)

26,608

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

#### Residential

#### Mortgage

#### 0.0%
Towd

Point

Mortgage

Trust

Series

2018-1,

Class

A1,

CMO,

ARM,

3.00%,

1/25/58 (1)

Towd

Point

Mortgage

Trust

Series

2019-HY3,

Class

M1,

CMO,

ARM,

1M

TSFR

+

1.614%,

5.941%,

10/25/59 (1)

510

520

554

#### Total

#### Non-U.S.

#### Government

#### Mortgage-Backed

#### Securities

#### (Cost

#### $46,941)

#### 45,291

#### U.S.

#### GOVERNMENT

#### &

#### AGENCY

#### MORTGAGE-BACKED

#### SECURITIES

#### 26.5%

#### U.S.

#### Government

#### Agency

#### Obligations

#### 20.8%
Federal

Home

Loan

Mortgage

2.50%,

4/1/30

-

6/1/30

3.00%,

12/1/42

-

4/1/47

2,489

2,227

3.50%,

3/1/42

-

3/1/46

1,879

1,754

4.00%,

9/1/40

-

8/1/45

673

648

4.50%,

8/1/39

-

10/1/41

5.00%,

9/1/33

-

8/1/40

5.50%,

1/1/35

-

12/1/39

6.00%,

10/1/32

-

8/1/38

6.50%,

12/1/28

-

1/1/36

7.00%,

11/1/30

-

6/1/32

Federal

Home

Loan

Mortgage,

ARM

RFUCCT1Y

+

1.625%,

6.899%,

4/1/37

RFUCCT1Y

+

1.726%,

7.597%,

7/1/35

RFUCCT1Y

+

1.75%,

6.75%,

2/1/35

RFUCCT1Y

+

1.916%,

6.916%,

2/1/37

RFUCCT1Y

+

1.944%,

6.579%,

12/1/36

RFUCCT1Y

+

2.031%,

6.796%,

11/1/36

Federal

Home

Loan

Mortgage,

UMBS

2.00%,

8/1/36

-

5/1/52

31,639

25,395

2.50%,

3/1/42

-

5/1/52

25,073

21,035

3.00%,

3/1/35

-

9/1/52

10,899

9,661

3.50%,

5/1/31

-

1/1/52

2,945

2,739

4.00%,

6/1/37

-

1/1/54

3,304

3,115

4.50%,

9/1/37

-

10/1/53

3,594

3,446

5.00%,

12/1/41

-

7/1/54

4,458

4,396

5.50%,

8/1/53

-

2/1/55

15,302

15,347

6.00%,

4/1/54

-

12/1/54

7,090

7,214

6.50%,

1/1/54

-

2/1/55

6,593

6,809

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

Federal

Home

Loan

Mortgage

Multifamily

Structured

PTC

2.952%,

2/25/27

4.40%,

10/25/30

6,065

6,114

Federal

Home

Loan

Mortgage

Multifamily

Structured

PTC,

ARM

2.347%,

11/25/31

10,520

9,331

3.71%,

9/25/32

4,545

4,341

4.43%,

2/25/33

3,725

3,720

Federal

National

Mortgage

Assn.

3.50%,

6/1/43

4.00%,

11/1/40

4.50%,

7/1/40

Federal

National

Mortgage

Assn.,

ARM

RFUCCT1Y

+

1.524%,

6.972%,

7/1/35

RFUCCT1Y

+

1.589%,

6.999%,

7/1/36

RFUCCT1Y

+

1.655%,

7.53%,

8/1/37

RFUCCT1Y

+

1.855%,

6.73%,

1/1/37

Federal

National

Mortgage

Assn.,

UMBS

1.50%,

4/1/37

-

1/1/42

7,136

6,180

2.00%,

8/1/28

-

5/1/52

80,439

66,227

2.50%,

5/1/30

-

1/1/54

47,066

39,946

3.00%,

10/1/32

-

9/1/52

24,355

21,930

3.50%,

11/1/25

-

1/1/52

18,393

16,987

4.00%,

6/1/37

-

9/1/52

14,287

13,494

4.50%,

9/1/35

-

2/1/54

13,677

13,252

5.00%,

11/1/33

-

7/1/53

4,189

4,151

5.50%,

12/1/34

-

10/1/54

9,799

9,873

6.00%,

2/1/33

-

8/1/54

16,984

17,339

6.50%,

1/1/32

-

1/1/55

9,007

9,315

7.00%,

2/1/30

-

11/1/36

7.50%,

12/1/30

—

—

UMBS,

TBA (8)

3.50%,

5/1/55

3,035

2,739

4.50%,

5/1/55

2,415

2,309

5.00%,

5/1/40

-

5/1/55

15,250

14,962

6.00%,

5/1/55

2,220

2,252

369,929

#### U.S.

#### Government

#### Obligations

#### 5.7%
Government

National

Mortgage

Assn.

1.50%,

12/20/36

-

5/20/37

719

640

2.00%,

1/20/51

-

5/20/52

20,489

16,719

2.50%,

8/20/50

-

1/20/52

19,784

16,866

3.00%,

9/15/42

-

6/20/52

16,379

14,549

3.50%,

9/15/41

-

7/20/52

12,009

11,027

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

4.00%,

2/15/41

-

10/20/52

10,123

9,497

4.50%,

9/15/34

-

4/20/53

6,134

5,941

5.00%,

1/20/33

-

6/20/49

2,815

2,809

5.50%,

10/20/32

-

9/20/54

1,781

1,801

6.00%,

8/15/33

-

11/20/52

1,856

1,892

6.50%,

4/15/26

-

8/15/29

7.50%,

8/15/25

-

3/15/32

8.50%,

7/20/26

—

—

Government

National

Mortgage

Assn.,

CMO

3.00%,

11/20/47

-

12/20/47

3.50%,

10/20/50

1,015

839

Government

National

Mortgage

Assn.,

TBA (8)

2.50%,

5/20/54

2,890

2,463

4.00%,

5/20/55

2,285

2,126

5.00%,

5/20/55

5,485

5,380

5.50%,

5/20/54

7,900

7,896

6.00%,

5/20/55

780

789

101,325

#### Total

#### U.S.

#### Government

#### &

#### Agency

#### Mortgage-Backed

#### Securities

#### (Cost

#### $494,332)

#### 471,254

#### U.S.

#### GOVERNMENT

#### AGENCY

#### OBLIGATIONS

#### (EXCLUDING

#### MORTGAGE-BACKED)

#### 37.7%

#### U.S.

#### Government

#### Agency

#### Obligations

#### 0.1%
Federal

National

Mortgage

Assn.,

6.25%,

5/15/29 (6)

Federal

National

Mortgage

Assn.,

6.625%,

11/15/30

500

568

942

#### U.S.

#### Treasury

#### Obligations

#### 37.6%
U.S.

Treasury

Bonds,

1.75%,

8/15/41

6,900

4,614

U.S.

Treasury

Bonds,

1.875%,

2/15/51

2,740

1,556

U.S.

Treasury

Bonds,

2.00%,

2/15/50

34,340

20,388

U.S.

Treasury

Bonds,

2.00%,

8/15/51

5,550

3,236

U.S.

Treasury

Bonds,

2.25%,

8/15/49

U.S.

Treasury

Bonds,

2.25%,

2/15/52

7,275

4,497

U.S.

Treasury

Bonds,

2.375%,

5/15/51

1,420

910

U.S.

Treasury

Bonds,

2.50%,

2/15/45

3,570

2,537

U.S.

Treasury

Bonds,

2.50%,

5/15/46

4,840

3,375

U.S.

Treasury

Bonds,

2.75%,

8/15/47

1,710

1,232

U.S.

Treasury

Bonds,

3.00%,

11/15/44

1,500

1,166

U.S.

Treasury

Bonds,

3.00%,

11/15/45

2,845

2,189

U.S.

Treasury

Bonds,

3.00%,

2/15/47

3,450

2,616

U.S.

Treasury

Bonds,

3.00%,

5/15/47

3,150

2,385

U.S.

Treasury

Bonds,

3.00%,

2/15/48

15,835

11,882

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

U.S.

Treasury

Bonds,

3.00%,

8/15/48

U.S.

Treasury

Bonds,

3.00%,

8/15/52

4,200

3,070

U.S.

Treasury

Bonds,

3.125%,

11/15/41

8,085

6,681

U.S.

Treasury

Bonds,

3.375%,

8/15/42

2,550

2,160

U.S.

Treasury

Bonds,

3.625%,

5/15/53

13,045

10,799

U.S.

Treasury

Bonds,

3.875%,

8/15/40

2,005

1,858

U.S.

Treasury

Bonds,

3.875%,

5/15/43

8,430

7,609

U.S.

Treasury

Bonds,

4.00%,

11/15/52

2,540

2,253

U.S.

Treasury

Bonds,

4.125%,

8/15/44

13,885

12,865

U.S.

Treasury

Bonds,

4.25%,

2/15/54

7,145

6,614

U.S.

Treasury

Bonds,

4.25%,

8/15/54

13,535

12,548

U.S.

Treasury

Bonds,

4.375%,

5/15/41

U.S.

Treasury

Bonds,

4.50%,

11/15/54

7,510

7,268

U.S.

Treasury

Bonds,

4.625%,

5/15/44

14,350

14,235

U.S.

Treasury

Bonds,

4.625%,

11/15/44

15,335

15,187

U.S.

Treasury

Bonds,

4.625%,

5/15/54

6,515

6,424

U.S.

Treasury

Bonds,

4.75%,

2/15/41

U.S.

Treasury

Bonds,

4.75%,

11/15/43

1,250

1,263

U.S.

Treasury

Bonds,

4.75%,

11/15/53 (9)

10,870

10,931

U.S.

Treasury

Notes,

0.50%,

8/31/27

U.S.

Treasury

Notes,

1.875%,

2/28/27

17,260

16,724

U.S.

Treasury

Notes,

2.25%,

8/15/27

9,805

9,517

U.S.

Treasury

Notes,

2.75%,

7/31/27

17,245

16,929

U.S.

Treasury

Notes,

2.75%,

8/15/32

14,000

12,926

U.S.

Treasury

Notes,

3.375%,

5/15/33

885

845

U.S.

Treasury

Notes,

3.625%,

5/31/28

14,000

14,009

U.S.

Treasury

Notes,

3.75%,

8/31/26

5,605

5,602

U.S.

Treasury

Notes,

3.75%,

12/31/28

14,550

14,603

U.S.

Treasury

Notes,

3.875%,

3/31/27

32,900

33,054

U.S.

Treasury

Notes,

4.00%,

2/29/28

10,285

10,395

U.S.

Treasury

Notes,

4.00%,

2/28/30

23,760

24,070

U.S.

Treasury

Notes,

4.00%,

3/31/30

19,700

19,948

U.S.

Treasury

Notes,

4.125%,

10/31/26

17,500

17,600

U.S.

Treasury

Notes,

4.125%,

9/30/27

6,210

6,288

U.S.

Treasury

Notes,

4.125%,

10/31/27

29,975

30,353

U.S.

Treasury

Notes,

4.125%,

10/31/29

11,500

11,705

U.S.

Treasury

Notes,

4.125%,

11/30/29

12,530

12,758

U.S.

Treasury

Notes,

4.25%,

2/28/29

6,895

7,041

U.S.

Treasury

Notes,

4.25%,

6/30/29

9,980

10,198

U.S.

Treasury

Notes,

4.25%,

1/31/30

16,980

17,377

U.S.

Treasury

Notes,

4.25%,

11/15/34

31,705

31,948

U.S.

Treasury

Notes,

4.375%,

11/30/28

835

855

U.S.

Treasury

Notes,

4.375%,

12/31/29

27,220

27,996

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par/Shares

#### $

#### Value
(Amounts

in

000s)

U.S.

Treasury

Notes,

4.375%,

5/15/34 (9)

18,400

18,752

U.S.

Treasury

Notes,

4.50%,

5/31/29

63,095

65,067

U.S.

Treasury

Notes,

4.50%,

11/15/33

7,900

8,143

U.S.

Treasury

Notes,

4.625%,

2/28/26

19,210

19,304

U.S.

Treasury

Notes,

4.625%,

6/30/26 (9)

16,000

16,141

U.S.

Treasury

Notes,

4.625%,

2/15/35

4,330

4,492

669,168

#### Total

#### U.S.

#### Government

#### Agency

#### Obligations

#### (Excluding

#### Mortgage-Backed)

#### (Cost

#### $698,958)

#### 670,110

#### SHORT-TERM

#### INVESTMENTS

#### 4.4%

#### Money

#### Market

#### Funds

#### 4.4%
T. Rowe

Price

Government

Reserve

Fund,

4.38% (10)(11)

77,591

77,591

#### Total

#### Short-Term

#### Investments

#### (Cost

#### $77,591)

#### 77,591

#### SECURITIES

#### LENDING

#### COLLATERAL

#### 0.3%

#### INVESTMENTS

#### IN

#### A

#### POOLED

#### ACCOUNT

#### THROUGH

#### SECURITIES

#### LENDING

#### PROGRAM

#### WITH

#### STATE

#### STREET

#### BANK

#### AND

#### TRUST

#### COMPANY 0.3%

#### Money

#### Market

#### Funds 0.3%
T. Rowe

Price

Government

Reserve

Fund,

4.38% (10)(11)

5,057

5,057

#### Total

#### Investments

#### in

#### a

#### Pooled

#### Account

#### through

#### Securities

#### Lending

#### Program

#### with

#### State

#### Street

#### Bank

#### and

#### Trust

#### Company

#### 5,057

#### Total

#### Securities

#### Lending

#### Collateral

#### (Cost

#### $5,057)

#### 5,057

#### Total

#### Investments

#### in

#### Securities

#### 102.0%

#### of

#### Net

#### Assets

#### (Cost

#### $1,892,620)

#### $

#### 1,814,490
‡

Par/Shares

and

Notional

Amount

are

denominated

in

U.S.

dollars

unless

otherwise

noted.

(1) Security

was

purchased

pursuant

to

Rule

144A

under

the

Securities

Act

of

1933

and

may

be

resold

in

transactions

exempt

from

registration

only

to

qualified

institutional

buyers.

Total

value

of

such

securities

at

period-end

amounts

to

$170,607

and

represents

9.6%

of

net

assets.

(2) Non-income

producing

(3) See

Note

2. Level

in

fair

value

hierarchy.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

.

.

.

.

.

.

.

.

.

.

(4) Security

cannot

be

offered

for

public

resale

without

first

being

registered

under

the

Securities

Act

of

1933

and

related

rules

("restricted

security").

Acquisition

date

represents

the

day

on

which

an

enforceable

right

to

acquire

such

security

is

obtained

and

is

presented

along

with

related

cost

in

the

security

description.

The

fund

may

have

registration

rights

for

certain

restricted

securities.

Any

costs

related

to

such

registration

are

generally

borne

by

the

issuer.

The

aggregate

value

of

restricted

securities

(excluding

144A

holdings)

at

period

end

amounts

to

$3,804

and

represents

0.2%

of

net

assets.

(5) Security

is

a

fix-to-float

security,

which

carries

a

fixed

coupon

until

a

certain

date,

upon

which

it

switches

to

a

floating

rate.

Reference

rate

and

spread

are

provided

if

the

rate

is

currently

floating.

(6) See

Note

.

All

or

a

portion

of

this

security

is

on

loan

at

April

30,

2025. (7) Insured

by

Assured

Guaranty

Municipal

Corporation

(8) See

Note

.

To-Be-Announced

purchase

commitment.

Total

value

of

such

securities

at

period-end

amounts

to

$40,916

and

represents

2.3%

of

net

assets.

(9) At

April

30,

2025,

all

or

a

portion

of

this

security

is

pledged

as

collateral

and/

or

margin

deposit

to

cover

future

funding

obligations.

(10) Seven-day

yield

(11) Affiliated

Companies

1M

TSFR

One

month

term

SOFR

(Secured

overnight

financing

rate)

3M

TSFR

Three

month

term

SOFR

(Secured

overnight

financing

rate)

ARM

Adjustable

Rate

Mortgage

(ARM);

rate

shown

is

effective

rate

at

period-end.

The

rates

for

certain

ARMs

are

not

based

on

a

published

reference

rate

and

spread

but

may

be

determined

using

a

formula

based

on

the

rates

of

the

underlying

loans.

CLO

Collateralized

Loan

Obligation

CMO

Collateralized

Mortgage

Obligation

DOT

Department

of

Transportation

FRN

Floating

Rate

Note

GO

General

Obligation

IDA

Industrial

Development

Authority/Agency

PTC

Pass-Through

Certificate

PTT

Pass-Through

Trust

RFUCCT1Y

Twelve

month

FTSE

USD

IBOR

Consumer

Cash

Fallback

SOFR30A

30-day

Average

SOFR

(Secured

overnight

financing

rate)

STEP

Stepped

coupon

bond

for

which

the

coupon

rate

of

interest

adjusts

on

specified

date(s);

rate

shown

is

effective

rate

at

period-end.

TBA

To-Be-Announced

UMBS

Uniform

Mortgage-Backed

Securities

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

.

.

.

.

.

.

.

.

.

.

VR

Variable

Rate;

rate

shown

is

effective

rate

at

period-end.

The

rates

for

certain

variable

rate

securities

are

not

based

on

a

published

reference

rate

and

spread

but

are

determined

by

the

issuer

or

agent

and

based

on

current

market

conditions.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Par

#### $

#### Value
(Cost

and

value

in

$000s)

#### TBA

#### SALES

#### COMMITMENTS

#### (0.1)%

#### U.S.

#### GOVERNMENT

#### &

#### AGENCY

#### MORTGAGE-BACKED

#### SECURITIES

#### (0.1)%

#### U.S.

#### Government

#### Agency

#### Obligations

#### (0.1)%
UMBS,

TBA,

3.00%,

5/1/55

2,565,000

(2,226)

#### Total

#### TBA

#### Sales

#### Commitments

#### (Proceeds

#### $(2,235))

#### (2,226)
T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

(Amounts

in

000s)

#### SWAPS

#### 0.1%

#### Description

#### Notional

#### Amount

#### $

#### Value

#### Initial

#### $

#### Value

#### \*\*

#### Unrealized

#### $

#### Gain/(Loss)

#### CENTRALLY

#### CLEARED

#### SWAPS

#### 0.1%

#### Credit

#### Default

#### Swaps,

#### Protection

#### Sold

#### 0.1%
Protection

Sold

(Relevant

Credit:

Markit

CDX.NA.IG-S43,

Year

Index),

Receive

1.00%

Quarterly,

Pay

upon

credit

default,

12/20/29

43,000

735

986

(251) Protection

Sold

(Relevant

Credit:

Markit

CDX.NA.IG-S44,

Year

Index),

Receive

1.00%

Quarterly,

Pay

upon

credit

default,

6/20/30

31,200

567

(70) #### Total

#### Centrally

#### Cleared

#### Credit

#### Default

#### Swaps,

#### Protection

#### Sold

#### (321)

#### Total

#### Centrally

#### Cleared

#### Swaps

#### (321)

#### Net

#### payments
(receipts)

#### of

#### variation

#### margin

#### to

#### date

#### 282

#### Variation

#### margin

#### receivable
(payable)

#### on

#### centrally

#### cleared

#### swaps

#### $

#### (39)
\*\*

Includes

interest

purchased

or

sold

but

not

yet

collected

of

$10.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### FUTURES

#### CONTRACTS
($000s)

#### Expiration

#### Date

#### Notional

#### Amount

#### Value

#### and

#### Unrealized

#### Gain
(Loss)

Long,

794

U.S.

Treasury

Notes

five

year

contracts

6/25

86,701

$

1,381

Long,

U.S.

Treasury

Notes

two

year

contracts

6/25

59,530

523

Long,

Ultra

U.S.

Treasury

Notes

ten

year

contracts

6/25

2,295

#### Net

#### payments
(receipts)

#### of

#### variation

#### margin

#### to

#### date

#### (1,790)

#### Variation

#### margin

#### receivable
(payable)

#### on

#### open

#### futures

#### contracts

#### $

#### 120
T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

The

accompanying

notes

are

an

integral

part

of

these

financial

statements.

#### AFFILIATED

#### COMPANIES
($000s)

The

fund

may

invest

in

certain

securities

that

are

considered

affiliated

companies.

As

defined

by

the

1940

Act,

an

affiliated

company

is

one

in

which

the

fund

owns

5%

or

more

of

the

outstanding

voting

securities,

or

a

company

that

is

under

common

ownership

or

control.

The

following

securities

were

considered

affiliated

companies

for

all

or

some

portion

of

the

six

months

ended

April

30,

2025. Net

realized

gain

(loss),

investment

income,

change

in

net

unrealized

gain/loss,

and

purchase

and

sales

cost

reflect

all

activity

for

the

period

then

ended.

#### Affiliate

#### Net

#### Realized

#### Gain
(Loss)

#### Change

#### in

#### Net

#### Unrealized

#### Gain/Loss

#### Investment

#### Income
T. Rowe

Price

Government

Reserve

Fund,

4.38%

$

—

$

—

$

1,131++

Totals

$

—#

$

—

$

1,131+

#### Supplementary

#### Investment

#### Schedule

#### Affiliate

#### Value

#### 10/31/24

#### Purchase

#### Cost

#### Sales

#### Cost

#### Value

#### 4/30/25
T. Rowe

Price

Government

Reserve

Fund,

4.38%

$

76,864

¤

¤

$

82,648

Total

$

82,648^

#

Capital

gain

distributions

from

underlying

Price

funds

represented

$0

of

the

net

realized

gain

(loss).

++

Excludes

earnings

on

securities

lending

collateral,

which

are

subject

to

rebates

and

fees

as

described

in

Note

.

+

Investment

income

comprised

$1,131

of

dividend

income

and

$0

of

interest

income.

¤

Purchase

and

sale

information

not

shown

for

cash

management

funds.

^

The

cost

basis

of

investments

in

affiliated

companies

was

$82,648.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

April

30,

2025

(Unaudited)

#### Statement

#### of

#### Assets

#### and

#### Liabilities

($000s,

except

shares

and

per

share

amounts)

#### Assets
Investments

in

securities,

at

value

(cost

$1,892,620)

$

1,814,490

Interest

receivable

15,061

Receivable

for

investment

securities

sold

11,533

Receivable

for

shares

sold

4,523

Variation

margin

receivable

on

futures

contracts

Cash

Other

assets

Total

assets

1,845,790

#### Liabilities
Payable

for

investment

securities

purchased

56,881

Obligation

to

return

securities

lending

collateral

5,057

TBA

Sales

Commitments

(proceeds

$2,235)

2,226

Payable

for

shares

redeemed

1,521

Investment

management

fees

payable

Due

to

affiliates

Variation

margin

payable

on

centrally

cleared

swaps

Other

liabilities

662

Total

liabilities

66,539

Commitments

and

Contingent

Liabilities

(note

6)

#### NET

#### ASSETS

#### $

#### 1,779,251
T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

April

30,

2025

(Unaudited)

#### Statement

#### of

#### Assets

#### and

#### Liabilities

($000s,

except

shares

and

per

share

amounts)

The

accompanying

notes

are

an

integral

part

of

these

financial

statements.

#### Net

#### Assets

#### Consist

#### of:
Total

distributable

earnings

(loss)

$

(179,224)

Paid-in

capital

applicable

to

184,491,113

shares

of

$0.0001

par

value

capital

stock

outstanding;

1,000,000,000

shares

authorized

1,958,475

#### NET

#### ASSETS

#### $

#### 1,779,251

#### NET

#### ASSET

#### VALUE

#### PER

#### SHARE

#### Investor

#### Class

#### (Net

#### assets:

#### $582,798;

#### Shares

#### outstanding:

#### 60,446,729)

#### $

#### 9.64

#### I

#### Class

#### (Net

#### assets:

#### $847,491;

#### Shares

#### outstanding:

#### 87,844,243)

#### $

#### 9.65

#### Z

#### Class

#### (Net

#### assets:

#### $348,962;

#### Shares

#### outstanding:

#### 36,200,141)

#### $

#### 9.64
T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

(Unaudited)

#### Statement

#### of

#### Operations

($000s)

Months

Ended

4/30/25

#### Investment

#### Income
(Loss)

Income

.

&nbsp;&nbsp;&nbsp;&nbsp;Interest

$

35,767

Dividend

1,131

Securities

lending

Other

Total

income

36,931

Expenses

Investment

management

583

Shareholder

servicing

Investor

Class

$

510

I

Class

625

Prospectus

and

shareholder

reports

Investor

Class

I

Class

Z

Class

Custody

and

accounting

Registration

Legal

and

audit

Directors

Miscellaneous

Waived

/

paid

by

Price

Associates

(249) Total

expenses

1,205

Net

investment

income

35,726

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

(Unaudited)

#### Statement

#### of

#### Operations

($000s)

The

accompanying

notes

are

an

integral

part

of

these

financial

statements.

Months

Ended

4/30/25

#### Realized

#### and

#### Unrealized

#### Gain

#### /

#### Loss
–

Net

realized

gain

(loss)

Securities

(6,493)

Futures

(2,042)

Swaps

Net

realized

loss

(8,438)

Change

in

net

unrealized

gain

/

loss

Securities

14,309

Futures

3,516

Swaps

(356) TBA

Sales

Commitments

Change

in

net

unrealized

gain

/

loss

17,478

Net

realized

and

unrealized

gain

/

loss

9,040

#### INCREASE

#### IN

#### NET

#### ASSETS

#### FROM

#### OPERATIONS

#### $

#### 44,766
T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

(Unaudited)

#### Statement

#### of

#### Changes

#### in

#### Net

#### Assets

($000s)

Months

Ended

4/30/25

Year

Ended

10/31/24

#### Increase
(Decrease)

#### in

#### Net

#### Assets
Operations

Net

investment

income

$

35,726

$

55,851

Net

realized

loss

(8,438)

(12,671)

Change

in

net

unrealized

gain

/

loss

17,478

86,871

Increase

in

net

assets

from

operations

44,766

130,051

Distributions

to

shareholders

Net

earnings

Investor

Class

(12,101)

(23,773)

I

Class

(17,838)

(26,636)

Z

Class

(6,243)

(5,834)

Decrease

in

net

assets

from

distributions

(36,182)

(56,243)

Capital

share

transactions

\*

Shares

sold

Investor

Class

93,474

172,392

I

Class

110,774

341,331

Z

Class

151,475

132,492

Distributions

reinvested

Investor

Class

11,678

22,969

I

Class

15,299

23,570

Z

Class

6,243

5,834

Shares

redeemed

Investor

Class

(122,216)

(207,123)

I

Class

(69,756)

(125,411)

Z

Class

(16,749)

(17,176)

Increase

in

net

assets

from

capital

share

transactions

180,222

348,878

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

(Unaudited)

#### Statement

#### of

#### Changes

#### in

#### Net

#### Assets

($000s)

The

accompanying

notes

are

an

integral

part

of

these

financial

statements.

Months

Ended

4/30/25

Year

Ended

10/31/24

#### Net

#### Assets
Increase

during

period

188,806

422,686

Beginning

of

period

1,590,445

1,167,759

#### End

#### of

#### period

#### $

#### 1,779,251

#### $

#### 1,590,445
\*Share

information

(000s)

Shares

sold

Investor

Class

9,773

17,992

I

Class

11,573

35,611

Z

Class

15,888

13,809

Distributions

reinvested

Investor

Class

1,217

2,396

I

Class

1,593

2,454

Z

Class

650

608

Shares

redeemed

Investor

Class

(12,775)

(21,695)

I

Class

(7,288)

(13,085)

Z

Class

(1,749)

(1,789)

Increase

in

shares

outstanding

18,882

36,301

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

Unaudited

#### NOTES

#### TO

#### FINANCIAL

#### STATEMENTS

T. Rowe

Price

QM

U.S.

Bond

Index

Fund,

Inc. (the

corporation)

is

registered

under

the

Investment

Company

Act

of

1940

(the

1940

Act).

The

QM

U.S.

Bond

Index

Fund

(the

fund)

is a

diversified, open-end

management

investment

company

established

by

the

corporation. The

fund

seeks to

provide

a

total

return

that

matches

or

incrementally

exceeds

the

performance

of

the

U.S.

investment-grade

bond

market.

The

fund

has three classes

of

shares:

the

QM

U.S.

Bond

Index

Fund

(Investor

Class),

the

QM

U.S.

Bond

Index

Fund–I

Class

(I

Class)

and

the

QM

U.S.

Bond

Index

Fund–Z

Class

(Z

Class).

I

Class

shares

require

a

$500,000

initial

investment

minimum,

although

the

minimum

generally

is

waived

or

reduced

for

financial

intermediaries,

eligible

retirement

plans,

and

certain

other

accounts.

The

Z

Class

is

only

available

to

funds

advised

by

T. Rowe

Price

Associates,

Inc.

and

its

affiliates

and

other

clients

that

are

subject

to

a

contractual

fee

for

investment

management

services. Each

class

has

exclusive

voting

rights

on

matters

related

solely

to

that

class;

separate

voting

rights

on

matters

that

relate

to

all

classes;

and,

in

all

other

respects,

the

same

rights

and

obligations

as

the

other

classes.

#### NOTE

#### 1

#### -

#### SIGNIFICANT

#### ACCOUNTING

#### POLICIES

#### Basis

#### of

#### Preparation
The fund

is

an

investment

company

and

follows

accounting

and

reporting

guidance

in

the

Financial

Accounting

Standards

Board

(FASB)

*Accounting* 

*Standards* 

*Codification* 

Topic

946

(ASC

946).

The

accompanying

financial

statements

were

prepared

in

accordance

with

accounting

principles

generally

accepted

in

the

United

States

of

America

(GAAP),

including,

but

not

limited

to,

ASC

946. GAAP

requires

the

use

of

estimates

made

by

management.

Management

believes

that

estimates

and

valuations

are

appropriate;

however,

actual

results

may

differ

from

those

estimates,

and

the

valuations

reflected

in

the

accompanying

financial

statements

may

differ

from

the

value

ultimately

realized

upon

sale

or

maturity.

#### Investment

#### Transactions,

#### Investment

#### Income,

#### and

#### Distributions
Investment

transactions

are

accounted

for

on

the

trade

date

basis.

Income

and

expenses

are

recorded

on

the

accrual

basis.

Realized

gains

and

losses

are

reported

on

the

identified

cost

basis. Premiums

and

discounts

on

debt

securities

are

amortized

for

financial

reporting

purposes. Paydown

gains

and

losses

are

recorded

as

an

adjustment

to

interest

income. Income

tax-related

interest

and

penalties,

if

incurred,

are

recorded

as

income

tax

expense. Dividends

received

from other

investment

companies are

reflected

as

dividend income;

capital

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

gain

distributions

are

reflected

as

realized

gain/loss. Dividend

income and

capital

gain

distributions

are

recorded

on

the

ex-dividend

date. Earnings

on

investments

recognized

as

partnerships

for

federal

income

tax

purposes

reflect

the

tax

character

of

such

earnings. Non-cash

dividends,

if

any,

are

recorded

at

the

fair

market

value

of

the

asset

received. Proceeds

from

litigation

payments,

if

any,

are

included

in

either

net

realized

gain

(loss)

or

change

in

net

unrealized

gain/loss

from

securities. Distributions

to

shareholders

are

recorded

on

the

ex-dividend

date. Income

distributions,

if

any, are

declared

by

each

class daily

and

paid

monthly. A

capital

gain

distribution,

if

any, may

also

be

declared

and

paid

by

the

fund

annually.

#### Class

#### Accounting
Shareholder

servicing,

prospectus,

and

shareholder

report

expenses

incurred

by

each

class

are

charged

directly

to

the

class

to

which

they

relate.

Expenses

common

to

all

classes

and

investment

income

are

allocated

to

the

classes

based

upon

the

relative

daily

net

assets

of

each

class's

settled

shares;

realized

and

unrealized

gains

and

losses

are

allocated

based

upon

the

relative

daily

net

assets

of

each

class's

outstanding

shares.

#### Capital

#### Transactions
Each

investor's

interest

in

the

net

assets

of the

fund

is

represented

by

fund

shares. The

fund's

net

asset

value

(NAV)

per

share

is

computed

at

the

close

of

the

New

York

Stock

Exchange

(NYSE),

normally

p.m.

Eastern

time,

each

day

the

NYSE

is

open

for

business.

However,

the

NAV

per

share

may

be

calculated

at

a

time

other

than

the

normal

close

of

the

NYSE

if

trading

on

the

NYSE

is

restricted,

if

the

NYSE

closes

earlier,

or

as

may

be

permitted

by

the

SEC.

Purchases

and

redemptions

of

fund

shares

are

transacted

at

the

next-computed

NAV

per

share,

after

receipt

of

the

transaction

order

by

T. Rowe

Price

Associates,

Inc.,

or

its

agents.

#### New

#### Accounting

#### Guidance
In December

2023,

the

FASB

issued

Accounting

Standards

Update

(ASU),

ASU

2023-09,

Income

Taxes

(Topic

740)

–

Improvements

to

Income

Taxes

Disclosures,

which

enhances

the

transparency

of

income

tax

disclosures.

The

ASU

requires

public

entities,

on

an

annual

basis,

to

provide

disclosure

of

specific

categories

in

the

rate

reconciliation,

as

well

as

disclosure

of

income

taxes

paid

disaggregated

by

jurisdiction.

The

amendments

under

this

ASU

are

required

to

be

applied

prospectively

and

are

effective

for

fiscal

years

beginning

after

December

15,

2024. Management

expects

that

adoption

of

the

guidance

will

not

have

a

material

impact

on

the

fund's

financial

statements.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Indemnification
In

the

normal

course

of

business, the

fund

may

provide

indemnification

in

connection

with

its

officers

and

directors,

service

providers,

and/or

private

company

investments. The

fund's

maximum

exposure

under

these

arrangements

is

unknown;

however,

the

risk

of

material

loss

is

currently

considered

to

be

remote.

#### NOTE

#### 2

#### -

#### VALUATION

#### Fair

#### Value
&nbsp;&nbsp;&nbsp;&nbsp;The

fund's

financial

instruments

are

valued

at

the

close

of

the

NYSE

and

are

reported

at

fair

value,

which

GAAP

defines

as

the

price

that

would

be

received

to

sell

an

asset

or

paid

to

transfer

a

liability

in

an

orderly

transaction

between

market

participants

at

the

measurement

date. The fund's

Board

of

Directors

(the

Board)

has

designated

T. Rowe

Price

Associates,

Inc.

as

the

fund's

valuation

designee

(Valuation

Designee).

Subject

to

oversight

by

the

Board,

the

Valuation

Designee

performs

the

following

functions

in

performing

fair

value

determinations:

assesses

and

manages

valuation

risks;

establishes

and

applies

fair

value

methodologies;

tests

fair

value

methodologies;

and

evaluates

pricing

vendors

and

pricing

agents.

The

duties

and

responsibilities

of

the

Valuation

Designee

are

performed

by

its

Valuation

Committee. The

Valuation

Designee provides

periodic

reporting

to

the

Board

on

valuation

matters.

Various

valuation

techniques

and

inputs

are

used

to

determine

the

fair

value

of

financial

instruments.

GAAP

establishes

the

following

fair

value

hierarchy

that

categorizes

the

inputs

used

to

measure

fair

value:

Level

–

quoted

prices

(unadjusted)

in

active

markets

for

identical

financial

instruments

that

the

fund

can

access

at

the

reporting

date

Level

–

inputs

other

than

Level

quoted

prices

that

are

observable,

either

directly

or

indirectly

(including,

but

not

limited

to,

quoted

prices

for

similar

financial

instruments

in

active

markets,

quoted

prices

for

identical

or

similar

financial

instruments

in

inactive

markets,

interest

rates

and

yield

curves,

implied

volatilities,

and

credit

spreads)

Level

–

unobservable

inputs

(including

the Valuation

Designee's assumptions

in

determining

fair

value)

Observable

inputs

are

developed

using

market

data,

such

as

publicly

available

information

about

actual

events

or

transactions,

and

reflect

the

assumptions

that

market

participants

would

use

to

price

the

financial

instrument.

Unobservable

inputs

are

those

for

which

market

data

are

not

available

and

are

developed

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

using

the

best

information

available

about

the

assumptions

that

market

participants

would

use

to

price

the

financial

instrument.

GAAP

requires

valuation

techniques

to

maximize

the

use

of

relevant

observable

inputs

and

minimize

the

use

of

unobservable

inputs.

When

multiple

inputs

are

used

to

derive

fair

value,

the

financial

instrument

is

assigned

to

the

level

within

the

fair

value

hierarchy

based

on

the

lowest-level

input

that

is

significant

to

the

fair

value

of

the

financial

instrument.

Input

levels

are

not

necessarily

an

indication

of

the

risk

or

liquidity

associated

with

financial

instruments

at

that

level

but

rather

the

degree

of

judgment

used

in

determining

those

values.

#### Valuation

#### Techniques
Debt

securities

generally

are

traded

in

the over-the-

counter

(OTC)

market

and

are

valued

at

prices

furnished

by

independent

pricing

services

or

by

broker

dealers

who

make

markets

in

such

securities.

When

valuing

securities,

the

independent

pricing

services

consider

factors

such

as,

but

not

limited

to,

the

yield

or

price

of

bonds

of

comparable

quality,

coupon,

maturity,

and

type,

as

well

as

prices

quoted

by

dealers

who

make

markets

in

such

securities.

Investments

in

mutual

funds

are

valued

at

the

mutual

fund's

closing

NAV

per

share

on

the

day

of

valuation.

Futures

contracts

are

valued

at

closing

settlement

prices.

Swaps

are

valued

at

prices

furnished

by

an

independent

pricing

service

or

independent

swap

dealers.

Assets

and

liabilities

other

than

financial

instruments,

including

short-term

receivables

and

payables,

are

carried

at

cost,

or

estimated

realizable

value,

if

less,

which

approximates

fair

value.

Investments

for

which

market

quotations are

not

readily

available

or

deemed

unreliable

are

valued

at

fair

value

as

determined

in

good

faith

by

the

Valuation

Designee.

The

Valuation

Designee

has

adopted

methodologies

for

determining

the

fair

value

of

investments

for

which

market

quotations

are

not

readily

available

or

deemed

unreliable,

including

the

use

of

other

pricing

sources.

Factors

used

in

determining

fair

value

vary

by

type

of

investment

and

may

include

market

or

investment

specific

considerations.

The

Valuation

Designee typically

will

afford

greatest

weight

to

actual

prices

in

arm's

length

transactions,

to

the

extent

they

represent

orderly

transactions

between

market

participants,

transaction

information

can

be

reliably

obtained,

and

prices

are

deemed

representative

of

fair

value.

However,

the

Valuation

Designee may

also

consider

other

valuation

methods

such

as

market-based

valuation

multiples;

a

discount

or

premium

from

market

value

of

a

similar,

freely

traded

security

of

the

same

issuer;

discounted

cash

flows;

yield

to

maturity;

or

some

combination.

Fair

value

determinations

are

reviewed

on

a

regular

basis.

Because

any

fair

value

determination

involves

a

significant

amount

of

judgment,

there

is

a

degree

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

of

subjectivity

inherent

in

such

pricing

decisions. Fair

value

prices

determined

by

the

Valuation

Designee could

differ

from

those

of

other

market

participants,

and

it

is

possible

that

the

fair

value

determined

for

a

security

may

be

materially

different

from

the

value

that

could

be

realized

upon

the

sale

of

that

security.

#### Valuation

#### Inputs
&nbsp;&nbsp;&nbsp;&nbsp;The

following

table

summarizes

the

fund's

financial

instruments,

based

on

the

inputs

used

to

determine

their

fair

values

on

April

30,

2025

(for

further

detail

by

category,

please

refer

to

the

accompanying

Portfolio

of

Investments):

($000s)

#### Level

#### 1

#### Level

#### 2

#### Level

#### 3

#### Total

#### Value

#### Assets
Fixed

Income

Securities

$

—

$

1,621,614

$

—

$

1,621,614

Asset-Backed

Securities

—

62,928

2,009

64,937

Non-U.S.

Government

Mortgage-Backed

Securities

—

43,496

1,795

45,291

Short-Term

Investments

77,591

—

—

77,591

Securities

Lending

Collateral

5,057

—

—

5,057

Total

Securities

82,648

1,728,038

3,804

1,814,490

Futures

Contracts\*

1,910

—

—

1,910

Total

$

84,558

$

1,728,038

$

3,804

$

1,816,400

#### Liabilities
TBA

Sales

Commitments

$

—

$

2,226

$

—

$

2,226

Swaps\*

$

—

$

$

—

$

Total

$

—

$

2,547

$

—

$

2,547

Includes

Corporate

Bonds,

Foreign

Government

Obligations

&

Municipalities,

Municipal

Securities,

U.S.

Government

&

Agency

Mortgage-Backed

Securities

and

U.S.

Government

Agency

Obligations

(Excluding

Mortgage-Backed).

\*

The

fair

value

presented

includes

cumulative

gain

(loss)

on

open

futures

contracts

and

centrally

cleared

swaps;

however,

the

net

value

reflected

on

the

accompanying

Portfolio

of

Investments

is

only

the

unsettled

variation

margin

receivable

(payable)

at

that

date.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### NOTE

#### 3

#### -

#### DERIVATIVE

#### INSTRUMENTS
During

the

six

months ended

April

30,

2025,

the

fund

invested

in

derivative

instruments.

As

defined

by

GAAP,

a

derivative

is

a

financial

instrument

whose

value

is

derived

from

an

underlying

security

price,

foreign

exchange

rate,

interest

rate,

index

of

prices

or

rates,

or

other

variable;

it

requires

little

or

no

initial

investment

and

permits

or

requires

net

settlement

or

delivery

of

cash

or

other

assets.

The

fund

invests

in

derivatives

only

if

the

expected

risks

and

rewards

are

consistent

with

its

investment

objectives,

policies,

and

overall

risk

profile,

as

described

in

its

prospectus

and

Statement

of

Additional

Information.

The

fund

may

use

derivatives

for

a

variety

of

purposes

and

may

use

them

to

establish

both

long

and

short

positions

within

the

fund's

portfolio.

Potential

uses

include

to

hedge

against

declines

in

principal

value,

increase

yield,

invest

in

an

asset

with

greater

efficiency

and

at

a

lower

cost

than

is

possible

through

direct

investment,

to

enhance

return,

or

to

adjust

portfolio

duration

and

credit

exposure.

The

risks

associated

with

the

use

of

derivatives

are

different

from,

and

potentially

much

greater

than,

the

risks

associated

with

investing

directly

in

the

instruments

on

which

the

derivatives

are

based.

The

fund

values

its

derivatives

at

fair

value

and

recognizes

changes

in

fair

value

currently

in

its

results

of

operations.

Accordingly,

the

fund

does

not

follow

hedge

accounting,

even

for

derivatives

employed

as

economic

hedges.

Generally,

the

fund

accounts

for

its

derivatives

on

a

gross

basis.

It

does

not

offset

the

fair

value

of

derivative

liabilities

against

the

fair

value

of

derivative

assets

on

its

financial

statements,

nor

does

it

offset

the

fair

value

of

derivative

instruments

against

the

right

to

reclaim

or

obligation

to

return

collateral.

The

following

table

summarizes

the

fair

value

of

the

fund's

derivative

instruments

held

as

of

April

30,

2025,

and

the

related

location

on

the

accompanying

Statement

of

Assets

and

Liabilities,

presented

by

primary

underlying

risk

exposure:

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

Additionally,

the

amount

of

gains

and

losses

on

derivative

instruments

recognized

in

fund

earnings

during

the

six

months ended

April

30,

2025,

and

the

related

location

on

the

accompanying

Statement

of

Operations

is

summarized

in

the

following

table

by

primary

underlying

risk

exposure:

($000s)

#### Location

#### on

#### Statement

#### of

#### Assets

#### and

#### Liabilities

#### Fair

#### Value\*

#### Assets
Interest

rate

derivatives

Futures

$

1,910

\*

Total

$

1,910

\*

#### Liabilities
Credit

derivatives

Centrally

Cleared

Swaps

$

Total

$

\*

The

fair

value

presented

includes

cumulative

gain

(loss)

on

open

futures

contracts

and

centrally

cleared

swaps;

however,

the

value

reflected

on

the

accompanying

Statement

of

Assets

and

Liabilities

is

only

the

unsettled

variation

margin

receivable

(payable)

at

that

date.

($000s)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

#### Location

#### of

#### Gain
(Loss)

#### on

#### Statement

#### of

#### Operations

#### Futures

#### Swaps

#### Total

#### Realized

#### Gain
(Loss)

Interest

rate

derivatives

$

(2,042)

$

—

$

(2,042)

Credit

derivatives

—

Total

$

(2,042)

$

$

(1,945)

#### Change

#### in

#### Unrealized

#### Gain
(Loss)

Interest

rate

derivatives

$

3,516

$

—

$

3,516

Credit

derivatives

—

(356) (356) Total

$

3,516

$

(356) $

3,160

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Counterparty

#### Risk

#### and

#### Collateral
The

fund

invests

in

exchange-traded

and/or

centrally

cleared

derivative

contracts,

such

as

futures,

exchange-traded

options,

and

centrally

cleared

swaps.

Counterparty

risk

on

such

derivatives

is

minimal

because

the

clearinghouse

provides

protection

against

counterparty

defaults.

For

futures

and

centrally

cleared

swaps,

the

fund

is

required

to

deposit

collateral

in

an

amount

specified

by

the

clearinghouse

and

the

clearing

firm

(margin

requirement),

and

the

margin

requirement

must

be

maintained

over

the

life

of

the

contract.

Each

clearinghouse

and

clearing

firm,

in

its

sole

discretion,

may

adjust

the

margin

requirements

applicable

to

the

fund.

Collateral may

be

in

the

form

of

cash

or

debt

securities

issued

by

the

U.S.

government

or

related

agencies.

Cash

posted

by

the

fund

is

reflected

as

cash

deposits

in

the

accompanying

financial

statements

and

generally

is

restricted

from

withdrawal

by

the

fund;

securities

posted

by

the

fund

are

so

noted

in

the

accompanying

Portfolio

of

Investments;

both

remain

in

the

fund's

assets.

While

typically

not

sold

in

the

same

manner

as

equity

or

fixed

income

securities,

exchange-traded

or

centrally

cleared

derivatives

may

be

closed

out

only

on

the

exchange

or

clearinghouse

where

the

contracts

were

cleared.

This

ability

is

subject

to

the

liquidity

of

underlying

positions. As

of

April

30,

2025,

securities

valued

at $3,489,000

had

been

posted

by

the

fund

for

exchange-traded

and/or

centrally

cleared

derivatives.

#### Futures

#### Contracts
The

fund

is

subject

to interest

rate

risk in

the

normal

course

of

pursuing

its

investment

objectives

and

uses

futures

contracts

to

help

manage

such

risk.

The fund

may

enter

into

futures

contracts

to

manage

exposure

to

interest

rate

and

yield

curve

movements,

security

prices,

foreign

currencies,

credit

quality,

and

mortgage

prepayments;

as

an

efficient

means

of

adjusting

exposure

to

all

or

part

of

a

target

market;

to

enhance

income;

as

a

cash

management

tool;

or

to

adjust

portfolio

duration

and

credit

exposure. A

futures

contract

provides

for

the

future

sale

by

one

party

and

purchase

by

another

of

a

specified

amount

of

a

specific

underlying

financial

instrument

at

an

agreed-upon

price,

date,

time,

and

place.

The

fund

currently

invests

only

in

exchange-traded

futures,

which

generally

are

standardized

as

to

maturity

date,

underlying

financial

instrument,

and

other

contract

terms.

Payments

are

made

or

received

by

the

fund

each

day

to

settle

daily

fluctuations

in

the

value

of

the

contract

(variation

margin),

which

reflect

changes

in

the

value

of

the

underlying

financial

instrument.

Variation

margin

is

recorded

as

unrealized

gain

or

loss

until

the

contract

is

closed.

The

value

of

a

futures

contract

included

in

net

assets

is

the

amount

of

unsettled

variation

margin;

net

variation

margin

receivable

is

reflected

as

an

asset

and

net

variation

margin

payable

is

reflected

as

a

liability

on

the

accompanying

Statement

of

Assets

and

Liabilities.

When

a

contract

is

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

closed,

a

realized

gain

or

loss

is

recorded

on

the

accompanying

Statement

of

Operations.

Risks

related

to

the

use

of

futures

contracts

include

possible

illiquidity

of

the

futures

markets,

contract

prices

that

can

be

highly

volatile

and

imperfectly

correlated

to

movements

in

hedged

security

values

and/or

interest

rates,

and

potential

losses

in

excess

of

the

fund's

initial

investment.

During

the

six

months ended

April

30,

2025,

the

volume

of

the

fund's

activity

in

futures,

based

on

underlying

notional

amounts,

was

generally

between

6%

and

11%

of

net

assets.

#### Swaps
The

fund

is

subject

to

credit

risk in

the

normal

course

of

pursuing

its

investment

objectives

and

uses

swap

contracts

to

help

manage

such

risk.

The

fund

may

use

swaps

in

an

effort

to

manage

both

long

and

short

exposure

to

changes

in

interest

rates,

inflation

rates,

and

credit

quality;

to

adjust

overall

exposure

to

certain

markets;

to

enhance

total

return

or

protect

the

value

of

portfolio

securities;

to

serve

as

a

cash

management

tool;

or

to

adjust

portfolio

duration

and

credit

exposure.

Swap

agreements

can

be

settled

either

directly

with

the

counterparty

(bilateral

swap)

or

through

a

central

clearinghouse

(centrally

cleared

swap).

Fluctuations

in

the

fair

value

of

a

contract

are

reflected

in

unrealized

gain

or

loss

and

are

reclassified

to

realized

gain

or

loss

on

the

accompanying

Statement

of

Operations upon

contract

termination

or

cash

settlement.

Net

periodic

receipts

or

payments

required

by

a

contract

increase

or

decrease,

respectively,

the

value

of

the

contract

until

the

contractual

payment

date,

at

which

time

such

amounts

are

reclassified

from

unrealized

to

realized

gain

or

loss

on

the

accompanying

Statement

of

Operations.

For

bilateral

swaps,

cash

payments

are

made

or

received

by

the

fund

on

a

periodic

basis

in

accordance

with

contract

terms;

unrealized

gain

on

contracts

and

premiums

paid

are

reflected

as

assets

and

unrealized

loss

on

contracts

and

premiums

received

are

reflected

as

liabilities

on

the

accompanying

Statement

of

Assets

and

Liabilities.

For

bilateral

swaps,

premiums

paid

or

received

are

amortized

over

the

life

of

the

swap

and

are

recognized

as

realized

gain

or

loss

on

the

accompanying

Statement

of

Operations.

For

centrally

cleared

swaps,

payments

are

made

or

received

by

the

fund

each

day

to

settle

the

daily

fluctuation

in

the

value

of

the

contract

(variation

margin).

Accordingly,

the

value

of

a

centrally

cleared

swap

included

in

net

assets

is

the

unsettled

variation

margin;

net

variation

margin

receivable

is

reflected

as

an

asset

and

net

variation

margin

payable

is

reflected

as

a

liability

on

the

accompanying

Statement

of

Assets

and

Liabilities.

Credit

default

swaps

are

agreements

where

one

party

(the

protection

buyer)

agrees

to

make

periodic

payments

to

another

party

(the

protection

seller)

in

exchange

for

protection

against

specified

credit

events,

such

as

certain

defaults

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

and

bankruptcies

related

to

an

underlying

credit

instrument,

or

issuer

or

index

of

such

instruments.

Upon

occurrence

of

a

specified

credit

event,

the

protection

seller

is

required

to

pay

the

buyer

the

difference

between

the

notional

amount

of

the

swap

and

the

value

of

the

underlying

credit,

either

in

the

form

of

a

net

cash

settlement

or

by

paying

the

gross

notional

amount

and

accepting

delivery

of

the

relevant

underlying

credit.

For

credit

default

swaps

where

the

underlying

credit

is

an

index,

a

specified

credit

event

may

affect

all

or

individual

underlying

securities

included

in

the

index

and

will

be

settled

based

upon

the

relative

weighting

of

the

affected

underlying

security(ies)

within

the

index. Generally,

the

payment

risk

for

the

seller

of

protection

is

inversely

related

to

the

current

market

price

or

credit

rating

of

the

underlying

credit

or

the

market

value

of

the

contract

relative

to

the

notional

amount,

which

are

indicators

of

the

markets'

valuation

of

credit

quality.

As

of

April

30,

2025,

the

notional

amount

of

protection

sold

by

the

fund

totaled $74,200,000

(4.2%

of

net

assets),

which

reflects

the

maximum

potential

amount

the

fund

could

be

required

to

pay

under

such

contracts.

Risks

related

to

the

use

of

credit

default

swaps

include

the

possible

inability

of

the

fund

to

accurately

assess

the

current

and

future

creditworthiness

of

underlying

issuers,

the

possible

failure

of

a

counterparty

to

perform

in

accordance

with

the

terms

of

the

swap

agreements,

potential

government

regulation

that

could

adversely

affect

the

fund's

swap

investments,

and

potential

losses

in

excess

of

the

fund's

initial

investment.

During

the

six

months ended

April

30,

2025,

the

volume

of

the

fund's

activity

in

swaps,

based

on

underlying

notional

amounts,

was

generally

between

4%

and

7%

of

net

assets.

#### NOTE

#### 4

#### -

#### OTHER

#### INVESTMENT

#### TRANSACTIONS
Consistent

with

its

investment

objective, the

fund

engages

in

the

following

practices

to

manage

exposure

to

certain

risks

and/or

to

enhance

performance.

The

investment

objective,

policies,

program,

and

risk

factors

of the

fund

are

described

more

fully

in the

fund's prospectus

and

Statement

of

Additional

Information.

#### Restricted

#### Securities
The

fund

invests

in

securities

that

are

subject

to

legal

or

contractual

restrictions

on

resale.

Prompt

sale

of

such

securities

at

an

acceptable

price

may

be

difficult

and

may

involve

substantial

delays

and

additional

costs.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Collateralized

#### Loan

#### Obligations
The

fund

invests

in

collateralized

loan

obligations

(CLOs)

which

are

entities

backed

by

a

diversified

pool

of

syndicated

bank

loans.

The

cash

flows

of

the

CLO

can

be

split

into

multiple

segments,

called

"tranches"

or

"classes",

which

will

vary

in

risk

profile

and

yield.

The

riskiest

segments,

which

are

the

subordinate

or

"equity"

tranches,

bear

the

greatest

risk

of

loss

from

defaults

in

the

underlying

assets

of

the

CLO

and

serve

to

protect

the

other,

more

senior,

tranches.

Senior

tranches

will

typically

have

higher

credit

ratings

and

lower

yields

than

the

securities

underlying

the

CLO.

Despite

the

protection

from

the

more

junior

tranches,

senior

tranches

can

experience

substantial

losses.

#### Mortgage-Backed

#### Securities
The

fund

invests

in

mortgage-backed

securities

(MBS

or

pass-through

certificates)

that

represent

an

interest

in

a

pool

of

specific

underlying

mortgage

loans

and

entitle

the

fund

to

the

periodic

payments

of

principal

and

interest

from

those

mortgages.

MBS

may

be

issued

by

government

agencies

or

corporations,

or

private

issuers.

Most

MBS

issued

by

government

agencies

are

guaranteed;

however,

the

degree

of

protection

differs

based

on

the

issuer.

MBS are

sensitive

to

changes

in

economic

conditions

that

affect

the

rate

of

prepayments

and

defaults

on

the

underlying

mortgages;

accordingly,

the

value,

income,

and

related

cash

flows

from

MBS

may

be

more

volatile

than

other

debt

instruments.

#### TBA

#### Purchase,

#### Sale

#### Commitments

#### and

#### Forward

#### Settling

#### Mortgage

#### Obligations
The

fund

enters

into

to-be-announced

(TBA)

purchase

or

sale

commitments

(collectively,

TBA

transactions),

pursuant

to

which

it

agrees

to

purchase

or

sell,

respectively,

mortgage-backed

securities

for

a

fixed

unit

price,

with

payment

and

delivery

at

a

scheduled

future

date

beyond

the

customary

settlement

period

for

such

securities.

With

TBA

transactions,

the

particular

securities

to

be

received

or

delivered

by

the

fund

are

not

identified

at

the

trade

date;

however,

the

securities

must

meet

specified

terms,

including

rate

and

mortgage

term,

and

be

within

industry-accepted

"good

delivery"

standards.

The

fund

may

enter

into

TBA

transactions

with

the

intention

of

taking

possession

of

or

relinquishing

the

underlying

securities,

may

elect

to

extend

the

settlement

by

"rolling"

the

transaction,

and/or

may

use

TBA

transactions

to

gain

or

reduce

interim

exposure

to

underlying

securities.

To

mitigate

counterparty

risk,

the

fund

has

entered

into

Master

Securities

Forward

Transaction

Agreements

(MSFTA)

with

counterparties

that

provide

for

collateral

and

the

right

to

offset

amounts

due

to

or

from

those

counterparties

under

specified

conditions.

Subject

to

minimum

transfer

amounts,

collateral

requirements

are

determined

and

transfers

made

based

on

the

net

aggregate

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

unrealized

gain

or

loss

on

all

TBA

commitments

and

other

forward

settling

mortgage

obligations

with

a

particular

counterparty

(collectively,

MSFTA

Transactions).

At

any

time,

the

fund's

risk

of

loss

from

a

particular

counterparty

related

to

its

MSFTA

Transactions

is

the

aggregate

unrealized

gain

on

appreciated

MSFTA

Transactions

in

excess

of

unrealized

loss

on

depreciated

MSFTA

Transactions

and

collateral

received,

if

any,

from

such

counterparty. As

of

April

30,

2025,

securities

valued

at

$286,000 had

been

posted

by

the

fund

to

counterparties

for

MSFTA

Transactions. No

collateral

was

pledged

by

counterparties

to

the

fund

for

MSFTA

Transactions

as

of

April

30,

2025. #### Dollar

#### Rolls
The

fund

enters

into

dollar

roll

transactions,

pursuant

to

which

it

sells

a

mortgage-backed

TBA

or

security

and

simultaneously

agrees

to

purchase

a

similar,

but

not

identical,

TBA

with

the

same

issuer,

rate,

and

terms

on

a

later

date

at

a

set

price

from

the

same

counterparty.

The

fund

may

execute

a

"roll"

to

obtain

better

underlying

mortgage

securities

or

to

enhance

returns.

While

the

fund

may

enter

into

dollar

roll

transactions

with

the

intention

of

taking

possession

of

the

underlying

mortgage

securities,

it

may

also

close

a

contract

prior

to

settlement

or

"roll"

settlement

to

a

later

date

if

deemed

to

be

in

the

best

interest

of

shareholders.

Actual

mortgages

received

by

the

fund

may

be

less

favorable

than

those

anticipated.

The

fund

accounts

for

dollar

roll

transactions

as

purchases

and

sales,

which

has

the

effect

of

increasing

its

portfolio

turnover

rate.

#### Securities

#### Lending
The fund

may

lend

its

securities

to

approved

borrowers

to

earn

additional

income.

Its

securities

lending

activities

are

administered

by

a

lending

agent

in

accordance

with

a

securities

lending

agreement.

Security

loans

generally

do

not

have

stated

maturity

dates,

and

the

fund

may

recall

a

security

at

any

time.

The

fund

receives

collateral

in

the

form

of

cash

or

U.S.

government

securities.

Collateral

is

maintained

over

the

life

of

the

loan

in

an

amount

not

less

than

the

value

of

loaned

securities;

any

additional

collateral

required

due

to

changes

in

security

values

is

delivered

to

the

fund

the

next

business

day.

Cash

collateral

is

invested

in

accordance

with

investment

guidelines

approved

by

fund

management.

Additionally,

the

lending

agent

indemnifies

the

fund

against

losses

resulting

from

borrower

default.

Although

risk

is

mitigated

by

the

collateral

and

indemnification,

the

fund

could

experience

a

delay

in

recovering

its

securities

and

a

possible

loss

of

income

or

value

if

the

borrower

fails

to

return

the

securities,

collateral

investments

decline

in

value,

and

the

lending

agent

fails

to

perform.

Securities

lending

revenue

consists

of

earnings

on

invested

collateral

and

borrowing

fees,

net

of

any

rebates

to

the

borrower,

compensation

to

the

lending

agent,

and

other

administrative

costs.

In

accordance

with

GAAP,

investments

made

with

cash

collateral

are

reflected

in

the

accompanying

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

financial

statements,

but

collateral

received

in

the

form

of

securities

is

not.

At

April

30,

2025,

the

value

of

loaned

securities

was

$4,848,000,

including

securities

sold

but

not

yet

settled,

which

are

not

reflected

in

the

accompanying

Portfolio

of

Investments;

the

value

of

cash

collateral

and

related

investments

was

$5,057,000.

#### Other
Purchases

and

sales

of

portfolio

securities

other

than

in-kind

transactions,

if

any, short-term

and

U.S.

government securities

aggregated $102,716,000 and

$157,238,000,

respectively,

for

the

six

months ended

April

30,

2025. Purchases

and

sales

of

U.S.

government

securities

aggregated $634,652,000 and

$420,955,000,

respectively,

for

the

six

months ended

April

30,

2025. #### NOTE

#### 5

#### -

#### FEDERAL

#### INCOME

#### TAXES
Generally,

no

provision

for

federal

income

taxes

is

required

since

the

fund

intends

to continue

to

qualify

as

a

regulated

investment

company

under

Subchapter

M

of

the

Internal

Revenue

Code

and

distribute

to

shareholders

all

of

its taxable

income

and

gains.

Distributions

determined

in

accordance

with

federal

income

tax

regulations

may

differ

in

amount

or

character

from

net

investment

income

and

realized

gains

for

financial

reporting

purposes.

Financial

reporting

records

are

adjusted

for

permanent

book/tax

differences

to

reflect

tax

character

but

are

not

adjusted

for

temporary

differences.

The

amount

and

character

of

tax-basis

distributions

and

composition

of

net

assets

are

finalized

at

fiscal

year-end;

accordingly,

tax-basis

balances

have

not

been

determined

as

of

the

date

of

this

report.

The

fund

intends

to

retain

realized

gains

to

the

extent

of

available

capital

loss

carryforwards.

Net

realized

capital

losses

may

be

carried

forward

indefinitely

to

offset

future

realized

capital

gains.

As

of

October

31,

2024,

the

fund

had

$92,531,000

of

available

capital

loss

carryforwards.

At

April

30,

2025,

the

cost

of

investments

(including

derivatives,

if

any)

for

federal

income

tax

purposes

was

$1,894,655,000.

Net

unrealized

loss

aggregated

$79,249,000

at

period-end,

of

which

$14,733,000

related

to

appreciated

investments

and

$93,982,000

related

to

depreciated

investments.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### NOTE

#### 6

#### -

#### RELATED

#### PARTY

#### TRANSACTIONS
The

fund

is

managed

by

T. Rowe

Price

Associates,

Inc.

(Price

Associates),

a

wholly

owned

subsidiary

of

T. Rowe

Price

Group,

Inc.

(Price

Group). The

investment

management

agreement

between

the

fund

and

Price

Associates

provides

for

an

annual

investment

management

fee

equal

to 0.07%

of

the

fund's

average

daily

net

assets.

The

fee

is

computed

daily

and

paid

monthly.

The

Investor

Class

is

subject

to

a

contractual

expense

limitation

through

the

expense

limitation

date

indicated

in

the

table

below.

This

agreement

will

continue

through

the

expense

limitation

date

indicated

in

the

table

below,

and

may

be

renewed,

revised,

or

revoked

only

with

approval

of

the

fund's

Board.

During

the

limitation

period,

Price

Associates

is required

to

waive

or

pay

any

expenses

(excluding

interest;

expenses

related

to

borrowings,

taxes,

and

brokerage;

non-recurring,

extraordinary

expenses;

and

acquired

fund

fees

and

expenses)

that

would

otherwise

cause

the class's ratio

of

annualized

total

expenses

to

average

net

assets

(net

expense

ratio)

to

exceed

its

expense

limitation.

The

class

is

required

to

repay

Price

Associates

for

expenses

previously

waived/paid

to

the

extent

the

class's net

assets

grow

or

expenses

decline

sufficiently

to

allow

repayment

without

causing

the class's net

expense

ratio

(after

the

repayment

is

taken

into

account)

to

exceed

the

lesser

of:

(1) the

expense

limitation

in

place

at

the

time

such

amounts

were

waived;

or

(2) the class's

current

expense

limitation.

However,

no

repayment

will

be

made

more

than

three

years

after

the

date

of

a

payment

or

waiver.

The

I

Class

is

also

subject

to

an

operating

expense

limitation

(I

Class

Limit)

pursuant

to

which

Price

Associates

is

contractually

required

to

pay

all

operating

expenses

of

the

I

Class,

excluding

management

fees;

interest;

expenses

related

to

borrowings,

taxes,

and

brokerage; non-recurring,

extraordinary expenses; and

acquired

fund

fees

and

expenses, to

the

extent

such

operating

expenses,

on

an

annualized

basis,

exceed

the

I

Class

Limit. This

agreement

will

continue

through

the

expense

limitation

date

indicated

in

the

table

below,

and

may

be

renewed,

revised,

or

revoked

only

with

approval

of

the

fund's

Board.

The

I

Class

is

required

to

repay

Price

Associates

for

expenses

previously

paid

to

the

extent

the

class's

net

assets

grow

or

expenses

decline

sufficiently

to

allow

repayment

without

causing

the

class's

operating

expenses

(after

the

repayment

is

taken

into

account)

to

exceed

the

lesser

of:

(1) the

I

Class

Limit

in

place

at

the

time

such

amounts

were

paid;

or

(2) the

current

I

Class

Limit.

However,

no

repayment

will

be

made

more

than

three

years

after

the

date

of

a

payment

or

waiver.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

The

Z

Class

is

also

subject

to

a

contractual

expense

limitation

agreement

whereby

Price

Associates

has

agreed

to

waive

and/or

bear

all

of

the

Z

Class'

expenses

(excluding

interest;

expenses

related

to

borrowings,

taxes,

and

brokerage;

non-recurring,

extraordinary

expenses;

and

acquired

fund

fees

and

expenses)

in

their

entirety.

This

fee

waiver

and/or

expense

reimbursement

arrangement

is

expected

to

remain

in

place

indefinitely,

and

the

agreement

may

only

be

amended

or

terminated

with

approval

by

the

fund's

Board.

Expenses

of

the

fund

waived/paid

by

the

manager

are

not

subject

to

later

repayment

by

the

fund.

In

addition, the

fund

is

subject

to

a

permanent

contractual

expense

limitation,

pursuant

to

which

Price

Associates

is

required

to

waive or

pay

any

expenses

(excluding

interest;

expenses

related

to

borrowings,

taxes,

and

brokerage;

non-

recurring,

extraordinary

expenses;

and

acquired

fund

fees

and

expenses)

that

would

otherwise

cause

the class's

ratio

of

annualized

total

expenses

to

average

net

assets

(net

expense

ratio)

to

exceed

0.30%.

The

agreement

may

only

be

terminated

with

approval

by

the

fund's

shareholders.

Each

class is

required

to

repay

Price

Associates

for

expenses

previously

waived/paid

to

the

extent

the class's

net

assets

grow

or

expenses

decline

sufficiently

to

allow

repayment

without

causing

the class's

net

expense

ratio

(after

the

repayment

is

taken

into

account)

to

exceed

the

lesser

of:

(1) the

expense

limitation

in

place

at

the

time

such

amounts

were

waived;

or

(2) the class's

current

expense

limitation.

However,

no

repayment

will

be

made

more

than

three

years

after

the

date

of

a

payment

or

waiver. No

management

fees

were

waived

or

any

expenses

paid

under

this

arrangement

during the

six

months ended

April

30,

2025. Pursuant

to

these

agreements,

expenses

were waived/paid

by

and/or

repaid

to

Price

Associates

during

the six

months

ended April

30,

2025 as

indicated

in

the

table

below.

Including

these

amounts,

expenses

previously

waived/paid

by

Price

Associates

in

the

amount

of $675,000 remain

subject

to

repayment

by

the

fund

at

April

30,

2025. Any

repayment

of

expenses

previously

waived/paid

by

Price

Associates

during

the

period

would

be

included

in

the

net

investment

income

and

expense

ratios

presented

on

the

accompanying

Financial

Highlights.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

In

addition,

the

fund

has

entered

into

service

agreements

with

Price

Associates

and

two

wholly

owned

subsidiaries

of

Price

Associates,

each

an

affiliate

of

the

fund

(collectively,

Price).

Price

Associates

provides

certain

accounting

and

administrative

services

to

the

fund.

T. Rowe

Price

Services,

Inc.

provides

shareholder

and

administrative

services

in

its

capacity

as

the

fund's

transfer

and

dividend-disbursing

agent.

T. Rowe

Price

Retirement

Plan

Services,

Inc.

provides

subaccounting

and

recordkeeping

services

for

certain

retirement

accounts

invested

in

the

Investor

Class.

For

the

six

months

ended

April

30,

2025,

expenses

incurred

pursuant

to

these

service

agreements

were

$59,000

for

Price

Associates;

$280,000

for

T. Rowe

Price

Services,

Inc.;

and

$38,000

for

T. Rowe

Price

Retirement

Plan

Services,

Inc.

All

amounts

due

to

and

due

from

Price,

exclusive

of

investment

management

fees

payable,

are

presented

net

on

the

accompanying

Statement

of

Assets

and

Liabilities.

T. Rowe

Price

Investment

Services,

Inc.

(Investment

Services)

serves

as

distributor

to

the

fund.

Pursuant

to

an

underwriting

agreement,

no

compensation

for

any

distribution

services

provided

is

paid

to

Investment

Services

by

the

fund

(except

for

12b-1

fees

under

a

Board-approved

Rule

12b-1

plan).

Additionally,

the

fund

is

one

of

several

mutual

funds

in

which

certain

college

savings

plans

managed

by

Price

Associates invests.

As

approved

by

the

fund's

Board

of

Directors,

shareholder

servicing

costs

associated

with

each

college

savings

plan

are

borne

by

the

fund

in

proportion

to

the

average

daily

value

of

its

shares

owned

by

the

college

savings

plan.

Price

has

agreed

to waive/reimburse

shareholder

servicing

costs in

excess

of

0.05%

of

the

fund's

average

daily

value

of

its

shares

owned

by

the

college

savings

plan.

Any

amounts

waived/

paid

by

Price

under

this

voluntary

agreement

are

not

subject

to

repayment

by

the

fund.

Price

may

amend

or

terminate

this

voluntary

arrangement

at

any

time

without

prior

notice.

For

the

six

months ended

April

30,

2025,

the

fund

was

charged $43,000 for

shareholder

servicing

costs

related

to

the

college

savings

plans, of

which

$9,000

was

for

services

provided

by

Price.

All

amounts

due

to

and

due

from

Price,

exclusive

of

investment

management

fees

payable,

are

#### Investor

#### Class

#### I

#### Class

#### Z

#### Class
Expense

limitation/I

Class

Limit

0.25%

0.05%

0.00%

Expense

limitation

date

12/31/26

12/31/26

N/A

(Waived)/repaid

during

the

period

($000s)

$(87)

$(26)

$(136)

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

presented

net

on

the

accompanying

Statement

of

Assets

and

Liabilities. At

April

30,

2025,

approximately

17%

of

the

outstanding

shares

of

the

I

Class

were

held

by

college

savings

plans.

Mutual

funds,

trusts,

and

other

accounts

managed

by

Price

Associates

or

its

affiliates

(collectively,

Price

Funds

and

accounts)

may

invest

in

the

fund.

No

Price

fund

or

account

may

invest

for

the

purpose

of

exercising

management

or

control

over

the

fund.

At

April

30,

2025, 100%

of

the

Z

Class's

outstanding

shares

were

held

by

Price

Funds

and

accounts.

The fund

may

invest

its

cash

reserves

in

certain

open-end

management

investment

companies

managed

by

Price

Associates

and

considered

affiliates

of

the

fund:

the

T. Rowe

Price

Government

Reserve

Fund

or

the

T. Rowe

Price

Treasury

Reserve

Fund,

organized

as

money

market

funds

(together,

the

Price

Reserve

Funds).

The

Price

Reserve

Funds

are

offered

as

short-term

investment

options

to

mutual

funds,

trusts,

and

other

accounts

managed

by

Price

Associates

or

its

affiliates

and

are

not

available

for

direct

purchase

by

members

of

the

public.

Cash

collateral

from

securities

lending,

if

any,

is

invested

in

the

T. Rowe

Price

Government

Reserve Fund. The

Price

Reserve

Funds

pay

no

investment

management

fees.

The fund may

participate

in

securities

purchase

and

sale

transactions

with

other

funds

or

accounts

advised

by

Price

Associates

(cross

trades),

in

accordance

with

procedures

adopted

by the

fund's

Board

and

Securities

and

Exchange

Commission

rules,

which

require,

among

other

things,

that

such

purchase

and

sale

cross

trades

be

effected

at

the

independent

current

market

price

of

the

security.

During

the

six

months

ended

April

30,

2025,

the

fund

had

no

purchases

or

sales

cross

trades

with

other

funds

or

accounts

advised

by

Price

Associates.

#### NOTE

#### 7

#### -

#### SEGMENT

#### REPORTING
Operating segments

are

defined

as

components

of

a

company

that

engage

in

business

activities

and

for

which

discrete

financial

information

is

available

and

regularly

reviewed

by

the

chief

operating

decision

maker

(CODM)

in

deciding

how

to

allocate

resources

and

assess

performance.

The

Management

Committee

of

Price

Associates

acts

as

the

fund's

CODM.

The

fund

makes

investments

in

accordance

with

its

investment

objective

as

outlined

in

the

Prospectus

and

is

considered

one

reportable

segment

because

the

CODM

allocates

resources

and

assesses

the

operating

results

of

the

fund

on

the

whole.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

The

fund's

revenue

is

derived

from

investments

in

a

portfolio

of

securities.

The

CODM

allocates

resources

and

assesses

performance

based

on

the

operating

results

of

the

fund,

which

is

consistent

with

the

results

presented

in

the

statement

of

operations,

statement

of

changes

in

net

assets

and

financial

highlights.

The

CODM

compares

the

fund's

performance

to

its

benchmark

index

and

evaluates

the

positioning

of

the

fund

in

relation

to

its

investment

objective.

The

measure

of

segment

assets

is

net

assets

of

the

fund

which

is

disclosed

in

the

statement

of

assets

and

liabilities.

The accounting

policies

of

the

segment

are

the

same

as

those

described

in

the

summary

of

significant

accounting

policies.

The

financial

statements

include

all

details

of

the

segment

assets,

segment

revenue

and

expenses;

and

reflect

the

financial

results

of

the

segment.

#### NOTE

#### 8

#### -

#### OTHER

#### MATTERS
Unpredictable environmental,

political,

social

and

economic

events,

including

but

not

limited

to,

environmental

or

natural

disasters,

war

and

conflict

(including

Russia's

military

invasion

of

Ukraine

and

the

conflict

in

Israel,

Gaza

and

surrounding

areas),

terrorism,

geopolitical

developments

(including

trading

and

tariff

arrangements,

sanctions

and

cybersecurity

attacks),

and

public

health

epidemics

(including

the

global

outbreak

of

COVID-19)

and

similar

public

health

threats,

may

significantly

affect

the

economy

and

the

markets

and

issuers

in

which

a

fund

invests.

The

extent

and

duration

of

such

events

and

resulting

market

disruptions

cannot

be

predicted.

These

and

other

similar

events

may

cause

instability

across

global

markets,

including

reduced

liquidity

and

disruptions

in

trading

markets,

while

some

events

may

affect

certain

geographic

regions,

countries,

sectors,

and

industries

more

significantly

than

others,

and

exacerbate

other

pre-existing

political,

social,

and

economic

risks.

The

fund's

performance

could

be

negatively

impacted

if

the

value

of

a

portfolio

holding

were

harmed

by

these

or

such

events.

Management

actively

monitors

the

risks

and

financial

impacts

arising

from

such

events.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### APPROVAL

#### OF

#### INVESTMENT

#### MANAGEMENT

#### AGREEMENT
Each

year,

the

fund's

Board

of

Directors

(Board)

considers

the

continuation

of

the

investment

management

agreement

(Advisory

Contract)

between

the

fund

and

its

investment

adviser,

T. Rowe

Price

Associates,

Inc.

(Adviser).

In

that

regard,

at

a

meeting

held

on

March

12-13,

2025

(Meeting),

the

Board,

including

all

of

the

fund's

independent

directors

present

in

person

at

the

Meeting,

approved

the

continuation

of

the

fund's

Advisory

Contract.

At

the

Meeting,

the

Board

considered

the

factors

and

reached

the

conclusions

described

below

relating

to

the

selection

of

the

Adviser

and

the

approval

of

the

Advisory

Contract.

The

independent

directors

were

assisted

in

their

evaluation

of

the

Advisory

Contract

by

independent

legal

counsel

from

whom

they

received

separate

legal

advice

and

with

whom

they

met

separately.

In

providing

information

to

the

Board,

the

Adviser

was

guided

by

a

detailed

set

of

requests

for

information

submitted

by

independent

legal

counsel

on

behalf

of

the

independent

directors.

In

considering

and

approving

the

continuation

of

the

Advisory

Contract,

the

Board

considered

the

information

it

believed

was

relevant,

including,

but

not

limited

to,

the

information

discussed

below.

The

Board

considered

not

only

the

specific

information

presented

in

connection

with

the

Meeting

but

also

the

knowledge

gained

over

time

through

interaction

with

the

Adviser

about

various

topics.

The

Board

meets

regularly

and,

at

each

of

its

meetings,

covers

an

extensive

agenda

of

topics

and

materials

and

considers

factors

that

are

relevant

to

its

annual

consideration

of

the

renewal

of

the

T. Rowe

Price

funds'

advisory

contracts,

including

performance

and

the

services

and

support

provided

to

the

funds

and

their

shareholders.

#### Services

#### Provided

#### by

#### the

#### Adviser
The

Board

considered

the

nature,

quality,

and

extent

of

the

services

provided

to

the

fund

by

the

Adviser.

These

services

included,

but

were

not

limited

to,

directing

the

fund's

investments

in

accordance

with

its

investment

program

and

the

overall

management

of

the

fund's

portfolio,

as

well

as

a

variety

of

related

activities

such

as

financial,

investment

operations,

and

administrative

services;

compliance

and

infrastructure,

as

well

as

compliance

with

new

regulatory

requirements

(e.g.,

derivatives

and

liquidity

risk

management);

maintaining

the

fund's

records

and

registrations;

and

shareholder

communications.

The

Board

also

reviewed

the

background

and

experience

of

the

Adviser's

senior

management

team

and

investment

personnel

involved

in

the

management

of

the

fund,

as

well

as

the

Adviser's

compliance

record.

The

Board

concluded

that

the

information

it

considered

with

respect

to

the

nature,

quality,

and

extent

of

the

services

provided

by

the

Adviser,

as

well

as

the

other

factors

considered

at

the

Meeting,

supported

the

Board's

approval

of

the

continuation

of

the

Advisory

Contract.

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

#### Investment

#### Performance

#### of

#### the

#### Fund
The

Board

took

into

account

discussions

with

the

Adviser

and

detailed

reports

that

it

regularly

receives

throughout

the

year

on

relative

and

absolute

performance

for

the

T. Rowe

Price

funds.

In

connection

with

the

Meeting,

the

Board

reviewed

information

provided

by

the

Adviser

that

compared

the

fund's

total

returns,

as

well

as

a

wide

variety

of

other

previously

agreed-upon

performance

measures

and

market

data,

against

relevant

benchmark

indexes

and

peer

groups

of

funds

with

similar

investment

programs

for

various

periods

through

December

31,

2024. Additionally,

the

Board

reviewed

the

fund's

relative

performance

information

as

of

September

30,

2024,

which

ranked

the

returns

of

the

fund's

Investor

Class

for

various

periods

against

a

universe

of

funds

with

similar

investment

programs

selected

by

Broadridge,

an

independent

provider

of

mutual

fund

data.

In

the

course

of

its

deliberations,

the

Board

considered

performance

information

provided

throughout

the

year

and

in

connection

with

the

Advisory

Contract

review

at

the

Meeting,

as

well

as

information

provided

during

investment

review

meetings

conducted

with

portfolio

managers

and

senior

investment

personnel

during

the

course

of

the

year

regarding

the

fund's

performance.

The

Board

also

considered

relevant

factors,

such

as

overall

market

conditions

and

trends

that

could

adversely

impact

the

fund's

performance,

length

of

the

fund's

performance

track

record,

and

how

closely

the

fund's

strategies

align

with

its

benchmarks

and

peer

groups.

The

Board

concluded

that

the

information

it

considered

with

respect

to

the

fund's

performance,

as

well

as

the

other

factors

considered

at

the

Meeting,

supported

the

Board's

approval

of

the

continuation

of

the

Advisory

Contract.

#### Costs,

#### Benefits,

#### Profits,

#### and

#### Economies

#### of

#### Scale
The

Board

reviewed

detailed

information

regarding

the

revenues

received

by

the

Adviser

under

the

Advisory

Contract

and

other

direct

and

indirect

benefits

that

the

Adviser

(and

its

affiliates)

may

have

realized

from

its

relationship

with

the

fund.

In

considering

soft-dollar

arrangements,

the

Board

noted

that,

effective

January

1,

2024,

the

Adviser

began

using

brokerage

commissions

in

connection

with

certain

T. Rowe

Price

funds'

securities

transactions

to

pay

for

research

when

permissible,

and

the

Board

considered

that

the

Adviser

may

receive

some

benefit

from

soft-

dollar

arrangements

pursuant

to

which

research

is

received

from

broker-dealers

that

execute

the

applicable

fund's

portfolio

transactions.

The

Board

received

information

on

the

estimated

costs

incurred

and

profits

realized

by

the

Adviser

from

managing

the

T. Rowe

Price

funds.

The

Board

also

reviewed

estimates

of

the

profits

realized

from

managing

the

fund

in

particular,

and

the

Board

concluded

that

the

Adviser's

profits

were

reasonable

in

light

of

the

services

provided

to

the

fund.

#### APPROVAL

#### OF

#### INVESTMENT

#### MANAGEMENT

#### AGREEMENT
(continued)

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

The

Board

also

considered

whether

the

fund

benefits

under

the

fee

levels

set

forth

in

the

Advisory

Contract

or

otherwise

from

any

economies

of

scale

realized

by

the

Adviser.

Under

the

Advisory

Contract,

the

fund

pays

a

fee

to

the

Adviser

for

investment

management

services

based

on

the

fund's

average

daily

net

assets

and

the

fund

pays

its

own

expenses

of

operations.

The

fund's

shareholders

benefit

from

potential

economies

of

scale

through

a

decline

in

certain

operating

expenses

as

the

fund

grows

in

size.

However,

the

fund

is

also

subject

to

a

contractual

expense

limitation

that

requires

the

Adviser

to

waive

its

fees

and/or

bear

any

expenses

that

would

otherwise

cause

the

expenses

of

a

share

class

of

the

fund

to

exceed

a

certain

percentage

based

on

the

class's

net

assets.

The

expense

limitations

mitigate

the

potential

for

an

increase

in

operating

expenses

above

a

certain

level

that

could

impact

shareholders.

The

fund

also

offers

a

Z

Class,

which

serves

as

an

underlying

investment

within

certain

T. Rowe

Price

fund

of

fund

arrangements.

The

Adviser

waives

its

advisory

fee

on

the

Z

Class

and

waives

or

bears

the

Z

Class's

other

operating

expenses,

with

certain

exceptions.

The

Board

considered

whether

the

advisory

fee

and

operating

expense

waivers

on

the

Z

Class

may

present

a

means

for

cross-

subsidization

of

the

Z

Class

by

other

share

classes

of

the

fund.

In

that

regard,

the

Board

noted

that

the

Z

Class

operating

expenses

are

covered

by

the

all-inclusive

fees

charged

by

the

investing

T. Rowe

Price

fund

of

funds

and

that

any

Z

Class

operating

expenses

not

covered

by

the

investing

T. Rowe

Price

funds

of

funds'

fees

are

paid

by

the

Adviser

and

not

by

shareholders

of

any

other

share

class

of

the

fund.

In

addition,

the

Board

noted

that

the

fund

potentially

shares

in

indirect

economies

of

scale

through

the

Adviser's

ongoing

investments

in

its

business

in

support

of

the

T. Rowe

Price

funds,

including

investments

in

trading

systems,

technology,

and

regulatory

support

enhancements,

and

the

ability

to

possibly

negotiate

lower

fee

arrangements

with

third-party

service

providers.

The

Board

concluded

that

the

advisory

fee

structure

for

the

fund

provides

for

a

reasonable

sharing

of

benefits

from

any

economies

of

scale

with

the

fund's

investors.

#### Fees

#### and

#### Expenses
The

Board

was

provided

with

information

regarding

industry

trends

in

management

fees

and

expenses.

Among

other

things,

the

Board

reviewed

data

for

peer

groups

that

were

compiled

by

Broadridge,

which

compared:

(i) contractual

management

fees,

actual

management

fees,

nonmanagement

expenses,

and

total

expenses

of

the

Investor

Class

of

the

fund

with

a

group

of

competitor

funds

selected

by

Broadridge

(Expense

Group);

and

(ii) actual

management

fees,

nonmanagement

expenses,

and

total

expenses

of

the

Investor

Class

of

the

fund

with

a

broader

set

of

funds

within

the

Lipper

investment

classification

(Expense

Universe).

The

Board

#### APPROVAL

#### OF

#### INVESTMENT

#### MANAGEMENT

#### AGREEMENT
(continued)

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

considered

the

fund's

contractual

management

fee

rate,

actual

management

fee

rate

(which

reflects

the

management

fees

actually

received

from

the

fund

by

the

Adviser

after

any

applicable

waivers,

reductions,

or

reimbursements),

operating

expenses,

and

total

expenses

(which

reflect

the

net

total

expense

ratio

of

the

fund

after

any

waivers,

reductions,

or

reimbursements)

in

comparison

with

the

information

for

the

Broadridge

peer

groups.

Broadridge

generally

constructed

the

peer

groups

by

seeking

the

most

comparable

funds

based

on

similar

investment

classifications

and

objectives,

expense

structure,

asset

size,

and

operating

components

and

attributes

and

ranked

funds

into

quintiles,

with

the

first

quintile

representing

the

funds

with

the

lowest

relative

expenses

and

the

fifth

quintile

representing

the

funds

with

the

highest

relative

expenses.

The

information

provided

to

the

Board

indicated

that

the

fund's

contractual

management

fee

ranked

in

the

second

quintile

(Expense

Group),

the

fund's

actual

management

fee

rate

ranked

in

the

second

quintile

(Expense

Group

and

Expense

Universe),

and

the

fund's

total

expenses

ranked

in

the

fifth

quintile

(Expense

Group

and

Expense

Universe).

The

Board

also

reviewed

the

fee

schedules

for

other

investment

portfolios

with

similar

mandates

that

are

advised

or

subadvised

by

the

Adviser

and

its

affiliates,

including

separately

managed

accounts

for

institutional

and

individual

investors;

subadvised

funds;

and

other

sponsored

investment

portfolios,

including

collective

investment

trusts

and

pooled

vehicles

organized

and

offered

to

investors

outside

the

United

States.

The

fee

schedules,

which

are

subject

to

change,

may

be

negotiated

under

certain

circumstances

and

may

differ

across

regions.

Management

provided

the

Board

with

information

about

the

Adviser's

responsibilities

and

services

provided

to

subadvisory

and

other

institutional

account

clients,

including

information

about

how

the

requirements

and

economics

of

the

institutional

domestic

and

international

businesses

are

fundamentally

different

from

those

of

the

proprietary

mutual

fund

and

ETF

("registered

fund")

business.

The

Board

considered

information

showing

that

the

Adviser's

registered

fund

business

is

generally

more

complex

from

a

business

and

compliance

perspective

than

its

other

domestic

and

international

businesses

and

considered

various

relevant

factors,

such

as

the

broader

scope

of

operations

and

oversight,

more

extensive

shareholder

communication

infrastructure,

greater

asset

flows,

heightened

business

risks,

and

differences

in

applicable

laws

and

regulations

associated

with

the

Adviser's

proprietary

registered

fund

business.

In

assessing

the

reasonableness

of

the

fund's

management

fee

rate,

the

Board

considered

the

differences

in

the

nature

of

the

services

required

for

the

Adviser

to

manage

its

registered

fund

business

versus

managing

a

discrete

pool

of

assets

as

a

subadviser

to

another

institution's

mutual

fund

or

for

an

institutional

account

and

that

the

Adviser

generally

performs

significant

additional

services

and

assumes

greater

risk

in

managing

the

fund

and

other

T. Rowe

Price

funds

than

it

does

for

institutional

account

clients,

including

subadvised

funds.

#### APPROVAL

#### OF

#### INVESTMENT

#### MANAGEMENT

#### AGREEMENT
(continued)

T. ROWE

PRICE

QM

U.S.

Bond

Index

Fund

On

the

basis

of

the

information

provided

and

the

factors

considered,

the

Board

concluded

that

the

fees

paid

by

the

fund

under

the

Advisory

Contract

are

reasonable.

#### Approval

#### of

#### the

#### Advisory

#### Contract
As

noted,

the

Board

approved

the

continuation

of

the

Advisory

Contract.

No

single

factor

was

considered

in

isolation

or

to

be

determinative

to

the

decision.

Rather,

the

Board

concluded,

in

light

of

a

weighting

and

balancing

of

all

factors

considered,

that

it

was

in

the

best

interests

of

the

fund

and

its

shareholders

for

the

Board

to

approve

the

continuation

of

the

Advisory

Contract

(including

the

fees

to

be

charged

for

services

thereunder).

#### APPROVAL

#### OF

#### INVESTMENT

#### MANAGEMENT

#### AGREEMENT
(continued)

1307

Point

Street

Baltimore,

Maryland

21231

T. Rowe

Price

Investment

Services,

Inc.

*Call* 

*1-800-225-5132* 

*to* 

*request* 

*a* 

*prospectus* 

*or* 

*summary* 

*prospectus;* 

*each* 

*includes* 

*investment* 

*objectives,* 

*risks,* 

*fees,* 

*expenses,* 

*and* 

*other* 

*information* 

*that* 

*you* 

*should* 

*read* 

*and* 

*consider* 

*carefully* 

*before* 

*investing.*

F134-051

6/25

------

#### Item 8. Changes in and Disagreements with Accountants for Open-End Management Investment Companies.
Not applicable.

#### Item 9. Proxy Disclosures for Open-End Management Investment Companies.
Not applicable.

#### Item 10. Remuneration Paid to Directors, Officers, and Others of Open-End Management Investment Companies.
Remuneration paid to Directors is included in Item 7 of this Form N-CSR.

------

#### Item 11. Statement Regarding Basis for Approval of Investment Advisory Contract.
If applicable, see Item 7.

#### Item 12. Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies.
Not applicable.

#### Item 13. Portfolio Managers of Closed-End Management Investment Companies.
Not applicable.

#### Item 14. Purchases of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers.
Not applicable.

#### Item 15. Submission of Matters to a Vote of Security Holders.
There has been no change to the procedures by which shareholders may recommend nominees to the registrant's board of directors.

#### Item 16. Controls and Procedures.
(a) The registrant's principal executive officer and principal financial officer have evaluated the registrant's disclosure controls and procedures within 90 days of this filing and have concluded that the registrant's disclosure controls and procedures were effective, as of that date, in ensuring that information required to be disclosed by the registrant in this Form N-CSR was recorded, processed, summarized, and reported timely.

(b) The registrant's principal executive officer and principal financial officer are aware of no change in the registrant's internal control over financial reporting that occurred during the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting.

#### Item 17. Disclosure of Securities Lending Activities for Closed-End Management Investment Companies.
Not applicable.

#### Item 18. Recovery of Erroneously Awarded Compensation.
Not applicable.

#### Item 19. Exhibits.

---

| | |
|:---|:---|
| (a)(1) | The registrant's code of ethics pursuant to Item 2 of Form N-CSR is filed with the registrant's annual Form N-CSR. |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(2) | Listing standards relating to recovery of erroneously awarded compensation: Not applicable. |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(3) | [Separate certifications by the registrant's principal executive officer and principal financial officer, pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 and required by Rule 30a-2(a) under the Investment Company Act of 1940, are attached.](d944258dex99cert.htm) |

---

------

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

(b) [A certification by the registrant's principal executive officer and principal financial officer, pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 and required by Rule 30a-2(b) under the Investment Company Act of 1940, is attached.](d944258dex99906ce.htm)

------

#### SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

---

| | |
|:---|:---|
| T. Rowe Price QM U.S. Bond Index Fund, Inc. | T. Rowe Price QM U.S. Bond Index Fund, Inc. |
| By | /s/ David Oestreicher |
|  | David Oestreicher |
|  | Principal Executive Officer |
| Date | June 17, 2025 |

---

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

---

| | |
|:---|:---|
| By | /s/ David Oestreicher |
|  | David Oestreicher |
|  | Principal Executive Officer |
| Date | June 17, 2025 |

---

---

| | |
|:---|:---|
| By | /s/ Alan S. Dupski |
|  | Alan S. Dupski |
|  | Principal Financial Officer |
| Date | June 17, 2025 |

---

## Ex-99.Cert

**Item 19. (a)(3)** 

**<u>CERTIFICATIONS</u>** 

I, David Oestreicher, certify that:

1. I have reviewed this report on Form N-CSR of T. Rowe Price QM U.S.
Bond Index Fund;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state
a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report,
fairly present in all material respects the financial condition, results of operations, changes in net assets, and cash flows (if the financial statements are required to include a statement of cash flows) of the registrant as of, and for, the
periods presented in this report;

4. The registrant's other certifying officer(s) and I are responsible for establishing and maintaining
disclosure controls and procedures (as defined in rule 30a-3(c) under the Investment Company Act of 1940) and internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act of 1940) for the registrant and have:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a) Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be
designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is
being prepared;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b) Designed such internal control over financial reporting, or caused such internal control over financial
reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting
principles;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c) Evaluated the effectiveness of the registrant's disclosure controls and procedures and presented in
this report our conclusions about the effectiveness of the disclosure controls and procedures, as of a date within 90 days prior to the filing date of this report based on such evaluation; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d) Disclosed in this report any change in the registrant's internal control over financial reporting that
occurred during the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting; and

5. The registrant's other certifying officer(s) and I have disclosed to the registrant's auditors and
the audit committee of the registrant's board of directors (or persons performing the equivalent functions):

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a) All significant deficiencies and material weaknesses in the design or operation of internal control over
financial reporting which are reasonably likely to adversely affect the registrant's ability to record, process, summarize, and report financial information; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b) Any fraud, whether or not material, that involves management or other employees who have a significant role
in the registrant's internal control over financial reporting.

---

| | |
|:---|:---|
| Date: June 17, 2025 | /s/ David Oestreicher |
|  | David Oestreicher |
|  | Principal Executive Officer |

---

------

**<u>CERTIFICATIONS</u>** 

I, Alan S. Dupski, certify that:

1. I have reviewed this report on Form N-CSR of T. Rowe Price QM U.S.
Bond Index Fund;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state
a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report,
fairly present in all material respects the financial condition, results of operations, changes in net assets, and cash flows (if the financial statements are required to include a statement of cash flows) of the registrant as of, and for, the
periods presented in this report;

4. The registrant's other certifying officer(s) and I are responsible for establishing and maintaining
disclosure controls and procedures (as defined in rule 30a-3(c) under the Investment Company Act of 1940) and internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act of 1940) for the registrant and have:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a) Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be
designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is
being prepared;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b) Designed such internal control over financial reporting, or caused such internal control over financial
reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting
principles;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c) Evaluated the effectiveness of the registrant's disclosure controls and procedures and presented in
this report our conclusions about the effectiveness of the disclosure controls and procedures, as of a date within 90 days prior to the filing date of this report based on such evaluation; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d) Disclosed in this report any change in the registrant's internal control over financial reporting that
occurred during the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting; and

5. The registrant's other certifying officer(s) and I have disclosed to the registrant's auditors and
the audit committee of the registrant's board of directors (or persons performing the equivalent functions):

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a) All significant deficiencies and material weaknesses in the design or operation of internal control over
financial reporting which are reasonably likely to adversely affect the registrant's ability to record, process, summarize, and report financial information; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b) Any fraud, whether or not material, that involves management or other employees who have a significant role
in the registrant's internal control over financial reporting.

---

| | |
|:---|:---|
| Date: June 17, 2025 | /s/ Alan S. Dupski |
|  | Alan S. Dupski |
|  | Principal Financial Officer |

---

## Exhibit 99.906

**Item 19. (b)** 

**CERTIFICATION UNDER SECTION 906 OF SARBANES-OXLEY ACT OF 2002** 

Name of Issuer: T. Rowe Price QM U.S. Bond Index Fund

In connection with the Report on Form N-CSR for the above named Issuer, the undersigned hereby certifies, to the best of his knowledge, that:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1. The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange
Act of 1934;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2. The information contained in the Report fairly presents, in all material respects, the financial condition
and results of operations of the Issuer.

---

| | |
|:---|:---|
| Date: June 17, 2025 | /s/ David Oestreicher |
|  | David Oestreicher |
|  | Principal Executive Officer |
| Date: June 17, 2025 | /s/ Alan S. Dupski |
|  | Alan S. Dupski |
|  | Principal Financial Officer |

---