# EDGAR Filing Document

**Accession Number:** 0001223026
**File Stem:** 0000940400-26-012927
**Filing Date:** 2026-4
**Character Count:** 11823
**Document Hash:** 48c2a6e6f1281259df242f7ec2c88d80
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000940400-26-012927.hdr.sgml**: 20260401

**ACCESSION NUMBER**: 0000940400-26-012927

**CONFORMED SUBMISSION TYPE**: NPORT-P

**PUBLIC DOCUMENT COUNT**: 2

**CONFORMED PERIOD OF REPORT**: 20260130

**FILED AS OF DATE**: 20260401

**DATE AS OF CHANGE**: 20260401

**PERIOD START**: 20260430

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** PIONEER MUNICIPAL HIGH INCOME FUND, INC.
- **CENTRAL INDEX KEY:** 0001223026

**ORGANIZATION NAME:**
- **EIN:** 030512430
- **STATE OF INCORPORATION:** MD
- **FISCAL YEAR END:** 0430

**FILING VALUES:**
- **FORM TYPE:** NPORT-P
- **SEC ACT:** 1940 Act
- **SEC FILE NUMBER:** 811-21321
- **FILM NUMBER:** 26827358

**BUSINESS ADDRESS:**
- **STREET 1:** 60 STATE STREET
- **STREET 2:** 5TH FLOOR
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02109
- **BUSINESS PHONE:** 617-742-7825

**MAIL ADDRESS:**
- **STREET 1:** 60 STATE STREET
- **STREET 2:** 5TH FLOOR
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02109

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** PIONEER MUNICIPAL HIGH INCOME TRUST
- **DATE OF NAME CHANGE:** 20030314

## Nport-Ex

## Pioneer Municipal High Income Fund, Inc.
Schedule of Investments \| January 31, 2026

------

### Schedule of Investments \| 1/31/26
(unaudited)

---

| | | |
|:---|:---|:---|
| &nbsp;&nbsp;**Principal<br> Amount<br> USD ($)** |  | **Value** |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**UNAFFILIATED ISSUERS — 56.2%** |  |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**Municipal Bonds — 56.2% of Net Assets** |  |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**Pennsylvania — 13.7%** |  |
| 500,000+ | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Philadelphia Authority for Industrial Development, 5.50%, 6/1/49 (144A) | $415344 |
| 1,000,000+ | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Philadelphia Authority for Industrial Development, Global Leadership Academy Charter School Project, Series A, 5.00%, 11/15/50 | &nbsp;&nbsp; 665533 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**Total Pennsylvania** | **$1080877** |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**Rhode Island — 26.2%** |  |
| 5,900,000(a)+ | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Central Falls Detention Facility Corp., 7.25%, 7/15/35 | $2070900 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**Total Rhode Island** | **$2070900** |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**Texas — 16.3%** |  |
| 490,000+ | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Arlington Higher Education Finance Corp., LTTS Charter School, Universal Academy, 5.45%, 3/1/49 (144A) | $381872 |
| 1,000,000+ | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Arlington Higher Education Finance Corp., Universal Academy, Series A, 7.00%, 3/1/34 | &nbsp;&nbsp; 900929 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**Total Texas** | **$1282801** |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**Total Municipal Bonds<br> (Cost $8,793,766)** | **$4434578** |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**TOTAL INVESTMENTS IN UNAFFILIATED ISSUERS — 56.2%<br> (Cost $8,793,766)** | **$4434578** |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**OTHER ASSETS AND LIABILITIES — 43.8%** | $3454460 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**net assets — 100.0%** | **$7889038** |

---

(144A) The resale of such security is exempt from registration under Rule 144A of the Securities Act of 1933. Such securities may be resold normally to qualified institutional buyers. At January 31, 2026, the value
of these securities amounted to $797,216, or 10.1% of net assets.

(a) Security is in default. <br> + Security is valued using significant unobservable inputs (Level 3).

Various inputs are used in determining the value of the Fund's investments. These inputs are summarized in the three broad levels below.

Level 1 – unadjusted quoted prices in active markets for identical securities. <br> Level 2 – other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risks, etc.).

1Pioneer Municipal High Income Fund, Inc. \| 1/31/26

------

Level 3 – significant unobservable inputs (including the Adviser's own assumptions in determining fair value of investments).

The following is a summary of the inputs used as of January 31, 2026 in valuing the Fund's investments:

---

| | | | | |
|:---|:---|:---|:---|:---|
|  | **Level 1** | &nbsp;&nbsp;**Level 2** | &nbsp;&nbsp;**Level 3** | &nbsp;&nbsp;**Total** |
| Municipal Bonds | $— | &nbsp;&nbsp;$— | &nbsp;&nbsp;$4434578 | &nbsp;&nbsp;$4434578 |
| **Total Investments in Securities** | **$—** | &nbsp;&nbsp;**$—** | &nbsp;&nbsp;**$4434578** | &nbsp;&nbsp;**$4434578** |

---

The following is a reconciliation of assets valued using significant unobservable inputs (Level 3):

---

| | |
|:---|:---|
|  | **Municipal Bonds** |
| Balance as of 4/30/25 | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;$— |
| Realized gain (loss) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;— |
| Changed in unrealized appreciation (depreciation) | &nbsp;&nbsp;&nbsp;&nbsp;(751289) |
| Amortization Premium/Discount | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;4876 |
| Purchases | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;— |
| Sales | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;— |
| Transfers in to Level 3\* | &nbsp;&nbsp;&nbsp;5180991 |
| Transfers out of Level 3\* | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;— |
| **Balance as of 1/31/26** | **$4434578** |

---

---

| | | |
|:---|:---|:---|
| \* | &nbsp;&nbsp;Transfers are calculated on the beginning of period values. During the period ended January 31, 2026, securities valued at $5,180,991 were transferred from Level 2 to Level 3, due to valuing the securities using unobservable inputs. There were no other transfers between Levels 1, 2 and 3. | &nbsp;&nbsp;Transfers are calculated on the beginning of period values. During the period ended January 31, 2026, securities valued at $5,180,991 were transferred from Level 2 to Level 3, due to valuing the securities using unobservable inputs. There were no other transfers between Levels 1, 2 and 3. |
| Net change in unrealized appreciation (depreciation) of Level 3 investments still held and considered Level 3 at January 31, 2026: | Net change in unrealized appreciation (depreciation) of Level 3 investments still held and considered Level 3 at January 31, 2026: | &nbsp;&nbsp;$(751289) |

---

Pioneer Municipal High Income Fund, Inc. \| 1/31/262

## Form NPORT-P: Monthly Portfolio Investments Report

### NPORT-P: Part A: General Information

**Item A.1. Information about the Registrant.**

- **a. Name of Registrant:** Pioneer Municipal High Income Fund, Inc.

- **b. Investment Company Act file number:** 811-21321

- **c. CIK number of Registrant:** 0001223026

- **d. LEI of Registrant:** 5493009JYKCUKTUKGP36

- **e. Address and telephone number of Registrant.**

  - **Street Address 1:** 60 State Street

  - **City:** Boston

  - **State:** MA

  - **Foreign country:** US

  - **Zip / Postal Code:** 02109

  - **Telephone number:** 617-422-4947

**Item A.2. Information about the Series.**

- **a. Name of Series:** Pioneer Municipal High Income Fund, Inc.

- **c. LEI of Series:** 5493009JYKCUKTUKGP36

**Item A.3. Reporting period.**

- **a. Date of fiscal year-end:** 2026-04-30

- **b. Date as of which information is reported:** 2026-01-30

**Item A.4. Final filing**

Does the Fund anticipate that this will be its final filing on Form N-PORT? **No**

### Fund Information

**Total Assets:** $7931639.11

**Total Liabilities:** $115112.52

**Net Assets:** $7816526.59

**Cash Not Reported:** $2753237.50

**Currency Risk Metrics (dv01):**

- 

**Credit Spread Risk - Investment Grade (dv01):**

- **3-Month:** 0.00000000 | **1-Year:** 0.00000000 | **5-Year:** 0.00000000 | **10-Year:** 0.00000000 | **30-Year:** 0.00000000

**Credit Spread Risk - Non-Investment Grade (dv01):**

- **3-Month:** 0.00000000 | **1-Year:** 0.00000000 | **5-Year:** -84.00000000 | **10-Year:** 0.00000000 | **30-Year:** -1821.00000000

**Monthly Return Information**

| Class               | Month 1 Return (%)   | Month 2 Return (%)   | Month 3 Return (%)   |
|:---|:---|:---|:---|
| Class ID C000000000 |  |  |  |

**Monthly Gains & Losses**

| Period   | Net Realized Gain/Loss   | Net Unrealized Appreciation/Depreciation   |
|:---|:---|:---|
| Month 1  | $0.00                    | $-844319.34                                |
| Month 2  | $0.00                    | $4658.47                                   |
| Month 3  | $0.00                    | $761.45                                    |

### Schedule of Portfolio Investments

| Name                          | Title                                             | Identifiers                                   | Payoff Profile   | Asset Category   | Issuer Category   | Country   |   Balance | Units   | Value (USD)   | % of Net Assets   | Maturity Date   | Coupon Type   | Annualized Rate (%)   | Restricted?   |   Fair Value Level | Lending Status   |
|:---|:---|:---|:---|:---|:---|:---|---:|:---|:---|:---|:---|:---|:---|:---|---:|:---|
| CENTRL FALLS RI DETENTION FAC | Central Falls Detention Facility Corp             | CUSIP: 153457AX4<br>LEI: N/A                  | Long             | DBT              | MUN               | US        |   5900000 | PA      | $2070900.00   | 26.49%            | 2035-07-15      | Fixed         | 7.25%                 | No            |                  3 | On Loan: No      |
| PHILADELPHIA PA AUTH FOR INDL | Philadelphia Authority for Industrial Development | CUSIP: 71780CAC4<br>LEI: 549300DIY68KQZEW7M79 | Long             | DBT              | MUN               | US        |    500000 | PA      | $415343.57    | 5.31%             | 2049-06-01      | Fixed         | 5.50%                 | No            |                  3 | On Loan: No      |
| ARLINGTON TX HGR EDU FIN CORP | Arlington Higher Education Finance Corp           | CUSIP: 041806AM2<br>LEI: N/A                  | Long             | DBT              | MUN               | US        |   1000000 | PA      | $900929.34    | 11.53%            | 2034-03-01      | Fixed         | 7.00%                 | No            |                  3 | On Loan: No      |
| ARLINGTON TX HGR EDU FIN CORP | Arlington Higher Education Finance Corp           | CUSIP: 041806XD7<br>LEI: N/A                  | Long             | DBT              | MUN               | US        |    490000 | PA      | $381871.91    | 4.89%             | 2049-03-01      | Fixed         | 5.45%                 | No            |                  3 | On Loan: No      |
| DAVID ELLIS ACADEMY WEST MI   | David Ellis Academy-West                          | CUSIP: 238560AA4<br>LEI: N/A                  | Long             | DBT              | MUN               | US        |    945000 | PA      | $681277.38    | 8.72%             | 2045-06-01      | Fixed         | 5.25%                 | No            |                  3 | On Loan: No      |
| PHILADELPHIA PA AUTH FOR INDL | Philadelphia Authority for Industrial Development | CUSIP: 71780CAM2<br>LEI: 549300DIY68KQZEW7M79 | Long             | DBT              | MUN               | US        |   1000000 | PA      | $665532.81    | 8.51%             | 2050-11-15      | Fixed         | 5.00%                 | No            |                  3 | On Loan: No      |

### Signature

**Date Signed:** 2026-04-01

**Name of Applicant:** Pioneer Municipal High Income Fund, Inc.

**Signature:** Carol Trevino

**Name of Signer:** Carol Trevino

**Title:** Treasurer