# EDGAR Filing Document

**Accession Number:** 0001060517
**File Stem:** 0001410368-25-021479
**Filing Date:** 2025-11
**Character Count:** 14525
**Document Hash:** d1715ade4a464e95ac7dd97e3437009a
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001410368-25-021479.hdr.sgml**: 20251107

**ACCESSION NUMBER**: 0001410368-25-021479

**CONFORMED SUBMISSION TYPE**: N-MFP3

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20251031

**FILED AS OF DATE**: 20251107

**DATE AS OF CHANGE**: 20251107

**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:** 251461875

**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 Treasury Preferred Fund (Series ID: S000018677)

| Class ID   | Class Name                         | Ticker Symbol   |
|:---|:---|:---|
| C000051800 | UBS Select Treasury Preferred Fund | STPXX           |

# 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):** 2025-10-31

**Registrant Full Name:** UBS Series Funds

**CIK Number of Registrant:** 0001060517

**LEI of Registrant:** 54930058UKPXVB81RJ71

**Name of Series:** UBS Select Treasury Preferred Fund

**LEI of Series:** 549300DXQ8KM8WHPPG39

**EDGAR Series Identifier:** S000018677

**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:** $21589228839.98

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

- **Cash:** $0.00

- **Total Other Assets:** $0.00

- **Total Liabilities:** $84740903.70

- **Net Assets of Series:** $21504487936.28

- **Number of Shares Outstanding (Series):** 21504358071.3700

- **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 (%)   |
|:---|:---|:---|:---|:---|
| 2025-10-01 | $46310921832.51           | $47310921832.51            | 97.7000%                  | 99.8100%                   |
| 2025-10-02 | $45381244069.93           | $46381244069.93            | 97.6500%                  | 99.8000%                   |
| 2025-10-03 | $45331470985.26           | $46331470985.26            | 97.6300%                  | 99.7900%                   |
| 2025-10-06 | $46008160460.36           | $47008160460.36            | 97.6700%                  | 99.8000%                   |
| 2025-10-07 | $45594444987.94           | $46594444987.94            | 97.6500%                  | 99.7900%                   |
| 2025-10-08 | $45645845533.08           | $46645845533.08            | 97.6500%                  | 99.7900%                   |
| 2025-10-09 | $44831365176.64           | $45831365176.64            | 97.6100%                  | 99.7800%                   |
| 2025-10-10 | $44279340685.50           | $45279340685.50            | 97.5500%                  | 99.7600%                   |
| 2025-10-13 | $0.00                     | $0.00                      | 0.0000%                   | 0.0000%                    |
| 2025-10-14 | $43727683983.79           | $44727683983.79            | 97.5300%                  | 99.7600%                   |
| 2025-10-15 | $44035874208.19           | $45035874208.19            | 97.5600%                  | 99.7700%                   |
| 2025-10-16 | $44422826071.61           | $45422826071.61            | 97.5700%                  | 99.7700%                   |
| 2025-10-17 | $43872421718.52           | $44872421718.52            | 97.5300%                  | 99.7500%                   |
| 2025-10-20 | $43317116973.52           | $44317116973.52            | 97.5000%                  | 99.7500%                   |
| 2025-10-21 | $42606387305.68           | $43606387305.68            | 97.4600%                  | 99.7500%                   |
| 2025-10-22 | $42227842151.71           | $43227842151.71            | 97.4300%                  | 99.7400%                   |
| 2025-10-23 | $41401841699.10           | $42401841699.10            | 97.3800%                  | 99.7300%                   |
| 2025-10-24 | $41173954363.52           | $42173954363.52            | 97.3500%                  | 99.7100%                   |
| 2025-10-27 | $41432061387.77           | $42432061387.77            | 97.3700%                  | 99.7200%                   |
| 2025-10-28 | $41311306235.81           | $42311306235.81            | 97.3600%                  | 99.7200%                   |
| 2025-10-29 | $42758334829.59           | $42758334829.59            | 99.7200%                  | 99.7200%                   |
| 2025-10-30 | $41343449966.00           | $42343449966.00            | 97.3700%                  | 99.7200%                   |
| 2025-10-31 | $41233391114.63           | $42233391114.63            | 97.5800%                  | 99.9400%                   |

### 7-Day Gross Yield
| Date       | 7-Day Gross Yield   |
|:---|:---|
| 2025-10-01 | 4.1800%             |
| 2025-10-02 | 4.1800%             |
| 2025-10-03 | 4.1800%             |
| 2025-10-06 | 4.1700%             |
| 2025-10-07 | 4.1700%             |
| 2025-10-08 | 4.1600%             |
| 2025-10-09 | 4.1600%             |
| 2025-10-10 | 4.1500%             |
| 2025-10-13 | 0.0000%             |
| 2025-10-14 | 4.1500%             |
| 2025-10-15 | 4.1500%             |
| 2025-10-16 | 4.1600%             |
| 2025-10-17 | 4.1700%             |
| 2025-10-20 | 4.1700%             |
| 2025-10-21 | 4.1600%             |
| 2025-10-22 | 4.1600%             |
| 2025-10-23 | 4.1500%             |
| 2025-10-24 | 4.1500%             |
| 2025-10-27 | 4.1600%             |
| 2025-10-28 | 4.1600%             |
| 2025-10-29 | 4.1500%             |
| 2025-10-30 | 4.1400%             |
| 2025-10-31 | 4.1200%             |

### Daily Net Asset Value per Share (Series)
| Date       | Net Asset Value per Share   |
|:---|:---|
| 2025-10-01 | 1.0002                      |
|  |  |
| 2025-10-02 | 1.0002                      |
|  |  |
| 2025-10-03 | 1.0001                      |
|  |  |
| 2025-10-06 | 1.0001                      |
|  |  |
| 2025-10-07 | 1.0001                      |
|  |  |
| 2025-10-08 | 1.0001                      |
|  |  |
| 2025-10-09 | 1.0001                      |
|  |  |
| 2025-10-10 | 1.0001                      |
|  |  |
| 2025-10-13 | 0.0000                      |
|  |  |
| 2025-10-14 | 1.0001                      |
|  |  |
| 2025-10-15 | 1.0001                      |
|  |  |
| 2025-10-16 | 1.0001                      |
|  |  |
| 2025-10-17 | 1.0001                      |
|  |  |
| 2025-10-20 | 1.0001                      |
|  |  |
| 2025-10-21 | 1.0001                      |
|  |  |
| 2025-10-22 | 1.0001                      |
|  |  |
| 2025-10-23 | 1.0001                      |
|  |  |
| 2025-10-24 | 1.0001                      |
|  |  |
| 2025-10-27 | 1.0002                      |
|  |  |
| 2025-10-28 | 1.0002                      |
|  |  |
| 2025-10-29 | 1.0001                      |
|  |  |
| 2025-10-30 | 1.0001                      |
|  |  |
| 2025-10-31 | 1.0001                      |
|  |  |

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

### Class: Single Class

- **Minimum Initial Investment:** $50000000.00

- **Net Assets of Class:** $21504487936.28

- **Number of Shares Outstanding:** 21504358071.3700

- **Expense Reimbursement/Waiver:** 857487.00

**Daily Net Asset Value per Share (Class)**
| Date       | NAV per Share   |
|:---|:---|
| 2025-10-01 | 1.0002          |
|  |  |
| 2025-10-02 | 1.0002          |
|  |  |
| 2025-10-03 | 1.0001          |
|  |  |
| 2025-10-06 | 1.0001          |
|  |  |
| 2025-10-07 | 1.0001          |
|  |  |
| 2025-10-08 | 1.0001          |
|  |  |
| 2025-10-09 | 1.0001          |
|  |  |
| 2025-10-10 | 1.0001          |
|  |  |
| 2025-10-13 | 0.0000          |
|  |  |
| 2025-10-14 | 1.0001          |
|  |  |
| 2025-10-15 | 1.0001          |
|  |  |
| 2025-10-16 | 1.0001          |
|  |  |
| 2025-10-17 | 1.0001          |
|  |  |
| 2025-10-20 | 1.0001          |
|  |  |
| 2025-10-21 | 1.0001          |
|  |  |
| 2025-10-22 | 1.0001          |
|  |  |
| 2025-10-23 | 1.0001          |
|  |  |
| 2025-10-24 | 1.0001          |
|  |  |
| 2025-10-27 | 1.0002          |
|  |  |
| 2025-10-28 | 1.0002          |
|  |  |
| 2025-10-29 | 1.0001          |
|  |  |
| 2025-10-30 | 1.0001          |
|  |  |
| 2025-10-31 | 1.0001          |
|  |  |

**Daily Shareholder Flows**
| Date       | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| 2025-10-01 | $1051408219.63            | $515418392.95           |
| 2025-10-02 | $184191229.33             | $423702426.52           |
| 2025-10-03 | $357612653.63             | $197515009.09           |
| 2025-10-06 | $599615939.54             | $312077160.86           |
| 2025-10-07 | $332213461.83             | $365553494.53           |
| 2025-10-08 | $268519660.08             | $582806706.55           |
| 2025-10-09 | $208211477.92             | $508372162.39           |
| 2025-10-10 | $631053846.83             | $1131609078.38          |
| 2025-10-13 | $0.00                     | $0.00                   |
| 2025-10-14 | $257600454.60             | $607311483.96           |
| 2025-10-15 | $290369566.88             | $405587141.56           |
| 2025-10-16 | $822102047.96             | $267707325.69           |
| 2025-10-17 | $281969337.26             | $984536964.75           |
| 2025-10-20 | $87838604.86              | $961355088.69           |
| 2025-10-21 | $219972613.33             | $601693177.50           |
| 2025-10-22 | $140621214.68             | $716139923.55           |
| 2025-10-23 | $95796515.64              | $400150026.37           |
| 2025-10-24 | $144553207.82             | $274117531.34           |
| 2025-10-27 | $126680478.43             | $284416689.32           |
| 2025-10-28 | $287568780.97             | $264084657.44           |
| 2025-10-29 | $1366379851.12            | $646374014.63           |
| 2025-10-30 | $256832799.90             | $642706829.05           |
| 2025-10-31 | $203951519.66             | $718836645.82           |

**Total Gross Subscriptions (Month):** $8215063481.90

**Total Gross Redemptions (Month):** $11812071930.94

**7-Day Net Yield (Class)**
| Date       | 7-Day Net Yield   |
|:---|:---|
| 2025-10-01 | 4.0400%           |
| 2025-10-02 | 4.0400%           |
| 2025-10-03 | 4.0400%           |
| 2025-10-06 | 4.0400%           |
| 2025-10-07 | 4.0300%           |
| 2025-10-08 | 4.0200%           |
| 2025-10-09 | 4.0200%           |
| 2025-10-10 | 4.0100%           |
| 2025-10-13 | 0.0000%           |
| 2025-10-14 | 4.0100%           |
| 2025-10-15 | 4.0100%           |
| 2025-10-16 | 4.0200%           |
| 2025-10-17 | 4.0300%           |
| 2025-10-20 | 4.0300%           |
| 2025-10-21 | 4.0300%           |
| 2025-10-22 | 4.0200%           |
| 2025-10-23 | 4.0100%           |
| 2025-10-24 | 4.0100%           |
| 2025-10-27 | 4.0200%           |
| 2025-10-28 | 4.0200%           |
| 2025-10-29 | 4.0100%           |
| 2025-10-30 | 4.0000%           |
| 2025-10-31 | 3.9800%           |

**Beneficial/Record Owner Categories**
| Category   | Other Category   | Record Owner %   | Beneficial Owner %   |
|:---|:---|:---|:---|
| Other      | IND FID AS EXEC  | 7.6300%          | 0.0000%              |

## Part C: Schedule of Portfolio Securities

### Security 1: Treasury Master Fund

- **C.1 - Title:** Treasury Master Fund
- **C.6 - Investment Category:** Investment Company
- **Identifiers:** C.3 - CUSIP: 81699K911, C.3 - LEI: 549300XQ6V293JKF0677, C.5 - Other ID: 81699K911
- **C.18 - Value (incl. sponsor support):** $21589228839.98
- **C.18.a - Value (excl. sponsor support):** $21589228839.98
- **C.19 - Percentage of Net Assets:** 100.0000%
- **C.17 - Yield as of Reporting Date:** 0.0000%
- **C.11 - Maturity Date (WAM):** 2025-11-03
- **C.12 - Maturity Date (WAL):** 2025-11-03
- **C.13 - Final Legal Maturity Date:** 2025-11-03
- **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:** 2025-11-07

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

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

**Title of Signing Officer:** Vice President