# EDGAR Filing Document

**Accession Number:** 0001060517
**File Stem:** 0001410368-25-033530
**Filing Date:** 2025-12
**Character Count:** 12899
**Document Hash:** 42445109573cf13a1baaefe9bedacea7
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001410368-25-033530.hdr.sgml**: 20251205

**ACCESSION NUMBER**: 0001410368-25-033530

**CONFORMED SUBMISSION TYPE**: N-MFP3

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20251130

**FILED AS OF DATE**: 20251205

**DATE AS OF CHANGE**: 20251205

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** UBS Series Funds
- **CENTRAL INDEX KEY:** 0001060517

**ORGANIZATION NAME:**
- **EIN:** 134010447
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 0430

**FILING VALUES:**
- **FORM TYPE:** N-MFP3
- **SEC ACT:** 1940 Act
- **SEC FILE NUMBER:** 811-08767
- **FILM NUMBER:** 251552597

**BUSINESS ADDRESS:**
- **STREET 1:** C/O UBS ASSET MANAGEMENT (AMERICAS) LLC
- **STREET 2:** 787 SEVENTH AVENUE
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10019
- **BUSINESS PHONE:** 212-821-3000

**MAIL ADDRESS:**
- **STREET 1:** C/O UBS ASSET MANAGEMENT (AMERICAS) LLC
- **STREET 2:** 787 SEVENTH AVENUE
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10019

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** UBS MONEY SERIES
- **DATE OF NAME CHANGE:** 20020716

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** BRINSON MONEY SERIES
- **DATE OF NAME CHANGE:** 20010625

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MITCHELL HUTCHINS LIR MONEY SERIES
- **DATE OF NAME CHANGE:** 19990730

## Series and Classes Contracts Data

### UBS Select 100% US Treasury Institutional Fund (Series ID: S000084282)

| Class ID   | Class Name                                     | Ticker Symbol   |
|:---|:---|:---|
| C000248579 | UBS Select 100% US Treasury Institutional Fund | SIOXX           |

# Form N-MFP3: Monthly Schedule of Portfolio Holdings

## N-MFP: Filer Information
**Submission Type:** N-MFP3
**CIK:** 0001060517

### General Information

**Report for (YYYY-MM-DD):** 2025-11-30

**Registrant Full Name:** UBS Series Funds

**CIK Number of Registrant:** 0001060517

**LEI of Registrant:** 54930058UKPXVB81RJ71

**Name of Series:** 100% US Treasury Institutional Fund

**LEI of Series:** 529900KWG787B4G5P791

**EDGAR Series Identifier:** S000084282

**Total number of share classes in the series:** 1

**Is this the fund's final filing on Form N-MFP?:** No

**Has the fund acquired or merged with another fund?:** No

## Part A: Series-Level Information about the Fund

### Service Providers
| Role                          | Details                                                      | File/CIK Number   |
|:---|:---|:---|
| Investment Adviser            | UBS ASSET MANAGEMENT (AMERICAS) LLC                          | 801-34910         |
| Independent Public Accountant | Ernst & Young  LLP<br>City: New York<br>State: NY            |  |
| Administrator                 | UBS ASSET MANAGEMENT (AMERICAS) LLC                          |  |
| Transfer Agent                | BNY Mellon Investment Servicing (US) Inc.<br>CIK: 0000849542 | 084-01761         |

### Fund Characteristics & Assets

- **Securities Act File Number:** 333-52965

- **Is this a Feeder Fund?:** Yes

- **Is this a Master Fund?:** No

- **Is this series for insurance company separate accounts?:** No

- **Money Market Fund Category:** Government

- **Is this a Retail Money Market Fund?:** No

- **Is this a Government Money Market Fund?:** Yes

- **WAM:** 1 days

- **WAL:** 1 days

- **Total Value of Portfolio Securities:** $7582486430.43

- **Amortized Cost of Portfolio Securities:** $0.00

- **Cash:** $0.00

- **Total Other Assets:** $23055.15

- **Total Liabilities:** $25066475.25

- **Net Assets of Series:** $7557443010.33

- **Number of Shares Outstanding (Series):** 7557338541.9100

- **Does the fund seek to maintain a stable price per share?:** Yes

- **Stable Price Per Share:** $1.00

- **Is cash management vehicle an affiliated fund?:** No

- **Does the fund apply liquidity fees?:** No

### Daily & Weekly Liquid Assets
| Date       | Daily Liquid Assets ($)   | Weekly Liquid Assets ($)   | Daily Liquid Assets (%)   | Weekly Liquid Assets (%)   |
|:---|:---|:---|:---|:---|
| 2025-11-03 | $14580644085.25           | $14580644085.25            | 99.9700%                  | 99.9700%                   |
| 2025-11-04 | $14849953282.20           | $14849953282.20            | 99.9700%                  | 99.9700%                   |
| 2025-11-05 | $14970761478.66           | $14970761478.66            | 99.9600%                  | 99.9600%                   |
| 2025-11-06 | $14894817854.60           | $14894817854.60            | 99.9600%                  | 99.9600%                   |
| 2025-11-07 | $14931690618.09           | $14931690618.09            | 99.9600%                  | 99.9600%                   |
| 2025-11-10 | $15136049261.12           | $15136049261.12            | 99.9500%                  | 99.9500%                   |
| 2025-11-11 | $0.00                     | $0.00                      | 0.0000%                   | 0.0000%                    |
| 2025-11-12 | $15015338876.90           | $15015338876.90            | 99.9500%                  | 99.9500%                   |
| 2025-11-13 | $15106121851.60           | $15106121851.60            | 99.9500%                  | 99.9500%                   |
| 2025-11-14 | $15132346871.19           | $15132346871.19            | 99.9400%                  | 99.9400%                   |
| 2025-11-17 | $15321323603.34           | $15321323603.34            | 99.9500%                  | 99.9500%                   |
| 2025-11-18 | $15100140403.55           | $15100140403.55            | 99.9500%                  | 99.9500%                   |
| 2025-11-19 | $15273285402.14           | $15273285402.14            | 99.9500%                  | 99.9500%                   |
| 2025-11-20 | $15349921553.99           | $15349921553.99            | 99.9400%                  | 99.9400%                   |
| 2025-11-21 | $15326269934.62           | $15326269934.62            | 99.9400%                  | 99.9400%                   |
| 2025-11-24 | $15691648155.19           | $15691648155.19            | 99.9400%                  | 99.9400%                   |
| 2025-11-25 | $15490272381.81           | $15490272381.81            | 99.9400%                  | 99.9400%                   |
| 2025-11-26 | $15958750645.76           | $15958750645.76            | 99.9300%                  | 99.9300%                   |
| 2025-11-28 | $15609166107.07           | $15609166107.07            | 99.9300%                  | 99.9300%                   |

### 7-Day Gross Yield
| Date       | 7-Day Gross Yield   |
|:---|:---|
| 2025-11-03 | 4.0500%             |
| 2025-11-04 | 4.0400%             |
| 2025-11-05 | 4.0400%             |
| 2025-11-06 | 4.0400%             |
| 2025-11-07 | 4.0300%             |
| 2025-11-10 | 4.0300%             |
| 2025-11-11 | 0.0000%             |
| 2025-11-12 | 4.0200%             |
| 2025-11-13 | 4.0200%             |
| 2025-11-14 | 4.0100%             |
| 2025-11-17 | 4.0000%             |
| 2025-11-18 | 4.0000%             |
| 2025-11-19 | 4.0000%             |
| 2025-11-20 | 3.9900%             |
| 2025-11-21 | 3.9900%             |
| 2025-11-24 | 3.9800%             |
| 2025-11-25 | 3.9800%             |
| 2025-11-26 | 3.9700%             |
| 2025-11-28 | 3.9600%             |

### Daily Net Asset Value per Share (Series)
| Date       | Net Asset Value per Share   |
|:---|:---|
| 2025-11-03 | 1.0001                      |
|  |  |
| 2025-11-04 | 1.0001                      |
|  |  |
| 2025-11-05 | 1.0001                      |
|  |  |
| 2025-11-06 | 1.0002                      |
|  |  |
| 2025-11-07 | 1.0001                      |
|  |  |
| 2025-11-10 | 1.0001                      |
|  |  |
| 2025-11-11 | 0.0000                      |
|  |  |
| 2025-11-12 | 1.0001                      |
|  |  |
| 2025-11-13 | 1.0001                      |
|  |  |
| 2025-11-14 | 1.0001                      |
|  |  |
| 2025-11-17 | 1.0001                      |
|  |  |
| 2025-11-18 | 1.0001                      |
|  |  |
| 2025-11-19 | 1.0001                      |
|  |  |
| 2025-11-20 | 1.0001                      |
|  |  |
| 2025-11-21 | 1.0001                      |
|  |  |
| 2025-11-24 | 1.0001                      |
|  |  |
| 2025-11-25 | 1.0001                      |
|  |  |
| 2025-11-26 | 1.0001                      |
|  |  |
| 2025-11-28 | 1.0001                      |
|  |  |

## Part B: Class-Level Information about the Fund

### Class: Single Class

- **Minimum Initial Investment:** $1.00

- **Net Assets of Class:** $7557443010.33

- **Number of Shares Outstanding:** 7557338541.9100

- **Expense Reimbursement/Waiver:** 48614.00

**Daily Net Asset Value per Share (Class)**
| Date       | NAV per Share   |
|:---|:---|
| 2025-11-03 | 1.0001          |
|  |  |
| 2025-11-04 | 1.0001          |
|  |  |
| 2025-11-05 | 1.0001          |
|  |  |
| 2025-11-06 | 1.0002          |
|  |  |
| 2025-11-07 | 1.0001          |
|  |  |
| 2025-11-10 | 1.0001          |
|  |  |
| 2025-11-11 | 0.0000          |
|  |  |
| 2025-11-12 | 1.0001          |
|  |  |
| 2025-11-13 | 1.0001          |
|  |  |
| 2025-11-14 | 1.0001          |
|  |  |
| 2025-11-17 | 1.0001          |
|  |  |
| 2025-11-18 | 1.0001          |
|  |  |
| 2025-11-19 | 1.0001          |
|  |  |
| 2025-11-20 | 1.0001          |
|  |  |
| 2025-11-21 | 1.0001          |
|  |  |
| 2025-11-24 | 1.0001          |
|  |  |
| 2025-11-25 | 1.0001          |
|  |  |
| 2025-11-26 | 1.0001          |
|  |  |
| 2025-11-28 | 1.0001          |
|  |  |

**Daily Shareholder Flows**
| Date       | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| 2025-11-03 | $81297692.82              | $70802484.54            |
| 2025-11-04 | $59409891.51              | $47724245.46            |
| 2025-11-05 | $54800295.77              | $63827246.90            |
| 2025-11-06 | $74881068.81              | $47231358.02            |
| 2025-11-07 | $42139773.98              | $36642452.53            |
| 2025-11-10 | $51231602.58              | $61344072.34            |
| 2025-11-11 | $0.00                     | $0.00                   |
| 2025-11-12 | $59189614.20              | $43233552.08            |
| 2025-11-13 | $56057736.02              | $41825219.17            |
| 2025-11-14 | $77316347.47              | $52204991.76            |
| 2025-11-17 | $31552126.72              | $35188360.83            |
| 2025-11-18 | $57906565.99              | $34299307.85            |
| 2025-11-19 | $62015860.17              | $66738830.49            |
| 2025-11-20 | $160984497.62             | $42029025.91            |
| 2025-11-21 | $50419937.89              | $90788947.09            |
| 2025-11-24 | $42024331.56              | $111217765.49           |
| 2025-11-25 | $35226593.40              | $60038388.83            |
| 2025-11-26 | $87706524.05              | $43106547.83            |
| 2025-11-28 | $30133449.92              | $19632190.93            |

**Total Gross Subscriptions (Month):** $1114293910.48

**Total Gross Redemptions (Month):** $967874988.05

**7-Day Net Yield (Class)**
| Date       | 7-Day Net Yield   |
|:---|:---|
| 2025-11-03 | 3.8700%           |
| 2025-11-04 | 3.8600%           |
| 2025-11-05 | 3.8600%           |
| 2025-11-06 | 3.8600%           |
| 2025-11-07 | 3.8500%           |
| 2025-11-10 | 3.8500%           |
| 2025-11-11 | 0.0000%           |
| 2025-11-12 | 3.8400%           |
| 2025-11-13 | 3.8400%           |
| 2025-11-14 | 3.8300%           |
| 2025-11-17 | 3.8200%           |
| 2025-11-18 | 3.8200%           |
| 2025-11-19 | 3.8200%           |
| 2025-11-20 | 3.8100%           |
| 2025-11-21 | 3.8100%           |
| 2025-11-24 | 3.8000%           |
| 2025-11-25 | 3.8000%           |
| 2025-11-26 | 3.7900%           |
| 2025-11-28 | 3.7800%           |

## Part C: Schedule of Portfolio Securities

### Security 1: 100 [percent symbol] US Treasury Master Fund

- **C.1 - Title:** 100 [percent symbol] US Treasury Master Fund
- **C.6 - Investment Category:** Investment Company
- **Identifiers:** C.3 - CUSIP: 902656883, C.3 - LEI: 549300EBIIAXTNCMYQ69
- **C.18 - Value (incl. sponsor support):** $7582486430.43
- **C.18.a - Value (excl. sponsor support):** $7582486430.43
- **C.19 - Percentage of Net Assets:** 100.0000%
- **C.17 - Yield as of Reporting Date:** 0.0000%
- **C.11 - Maturity Date (WAM):** 2025-12-01
- **C.12 - Maturity Date (WAL):** 2025-12-01
- **C.13 - Final Legal Maturity Date:** 2025-12-01
- **Characteristics:** C.9 Eligible Security? Yes, C.14 Has Demand Feature? No, C.15 Has Guarantee? No, C.16 Has Enhancement? No, C.22 Is an Illiquid Security? No, C.20 Is a Daily Liquid Asset? Yes, C.21 Is a Weekly Liquid Asset? Yes, C.23 Categorized at Level 3? No

## N-MFP: Signatures

**Registrant:** UBS Series Funds

**Date:** 2025-12-05

**By:** /s/Rose Ann Bubloski

**Name of Signing Officer:** Rose Ann Bubloski

**Title of Signing Officer:** Vice President