# EDGAR Filing Document

**Accession Number:** 0001060517
**File Stem:** 0001145549-25-050839
**Filing Date:** 2025-8
**Character Count:** 13904
**Document Hash:** 86ae06a7c9640e7a69c67175a4d756e3
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001145549-25-050839.hdr.sgml**: 20250807

**ACCESSION NUMBER**: 0001145549-25-050839

**CONFORMED SUBMISSION TYPE**: N-MFP3

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20250731

**FILED AS OF DATE**: 20250807

**DATE AS OF CHANGE**: 20250807

**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:** 251193141

**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 Prime Preferred Fund (Series ID: S000052307)

| Class ID   | Class Name               | Ticker Symbol   |
|:---|:---|:---|
| C000164453 | UBS Prime Preferred Fund | UPPXX           |

# 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):** 2025-07-31

**Registrant Full Name:** UBS Series Funds

**CIK Number of Registrant:** 0001060517

**LEI of Registrant:** 54930058UKPXVB81RJ71

**Name of Series:** UBS Prime Preferred Fund

**LEI of Series:** 5493001YQBD9A4ZH6D79

**EDGAR Series Identifier:** S000052307

**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:** Prime

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

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

- **WAM:** 1 days

- **WAL:** 1 days

- **Total Value of Portfolio Securities:** $10136353390.00

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

- **Cash:** $0.00

- **Total Other Assets:** $0.00

- **Total Liabilities:** $37591847.20

- **Net Assets of Series:** $10098761542.80

- **Number of Shares Outstanding (Series):** 10098093822.6010

- **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 (%)   |
|:---|:---|:---|:---|:---|
| 2025-07-01 | $10781615128.38           | $13350752277.67            | 43.2400%                  | 53.5400%                   |
| 2025-07-02 | $9532477123.12            | $13440174778.02            | 38.3300%                  | 54.0400%                   |
| 2025-07-03 | $10157181811.59           | $13515297795.19            | 40.7100%                  | 54.1700%                   |
| 2025-07-07 | $10544175153.81           | $13626323587.41            | 42.3500%                  | 54.7200%                   |
| 2025-07-08 | $11300944362.11           | $13705034311.11            | 45.3500%                  | 55.0000%                   |
| 2025-07-09 | $11068584934.11           | $13734273256.11            | 44.3500%                  | 55.0300%                   |
| 2025-07-10 | $11073011997.42           | $13793807402.92            | 44.1500%                  | 55.0000%                   |
| 2025-07-11 | $10820583448.22           | $13498265092.22            | 43.2300%                  | 53.9300%                   |
| 2025-07-14 | $10830144239.97           | $13340275576.77            | 42.8600%                  | 52.7900%                   |
| 2025-07-15 | $11003270967.93           | $12942269628.43            | 44.0800%                  | 51.8500%                   |
| 2025-07-16 | $9180199116.61            | $13140789016.01            | 36.3800%                  | 52.0700%                   |
| 2025-07-17 | $9386086807.81            | $12757164842.61            | 37.5800%                  | 51.0700%                   |
| 2025-07-18 | $9447864676.25            | $12667146744.45            | 37.9500%                  | 50.8800%                   |
| 2025-07-21 | $9870142148.90            | $12778684052.66            | 39.7100%                  | 51.4100%                   |
| 2025-07-22 | $11503120274.07           | $13030542327.22            | 46.0300%                  | 52.1400%                   |
| 2025-07-23 | $10120935722.04           | $12857677626.52            | 40.6800%                  | 51.6900%                   |
| 2025-07-24 | $10352935866.79           | $12739989937.87            | 41.7100%                  | 51.3300%                   |
| 2025-07-25 | $10279881613.97           | $12559811699.47            | 41.5300%                  | 50.7400%                   |
| 2025-07-28 | $10953165441.04           | $12742245622.20            | 44.2600%                  | 51.4900%                   |
| 2025-07-29 | $11693763083.62           | $12750824826.54            | 47.2800%                  | 51.5600%                   |
| 2025-07-30 | $10797780477.28           | $12851269189.71            | 43.5900%                  | 51.8800%                   |
| 2025-07-31 | $10945382467.95           | $13048911140.66            | 43.9200%                  | 52.3700%                   |

### 7-Day Gross Yield
| Date       | 7-Day Gross Yield   |
|:---|:---|
| 2025-07-01 | 4.5000%             |
| 2025-07-02 | 4.5100%             |
| 2025-07-03 | 4.5000%             |
| 2025-07-07 | 4.5000%             |
| 2025-07-08 | 4.4900%             |
| 2025-07-09 | 4.4900%             |
| 2025-07-10 | 4.4800%             |
| 2025-07-11 | 4.4700%             |
| 2025-07-14 | 4.4700%             |
| 2025-07-15 | 4.4700%             |
| 2025-07-16 | 4.4700%             |
| 2025-07-17 | 4.4700%             |
| 2025-07-18 | 4.4800%             |
| 2025-07-21 | 4.4800%             |
| 2025-07-22 | 4.4800%             |
| 2025-07-23 | 4.4700%             |
| 2025-07-24 | 4.4700%             |
| 2025-07-25 | 4.4700%             |
| 2025-07-28 | 4.4800%             |
| 2025-07-29 | 4.4800%             |
| 2025-07-30 | 4.4900%             |
| 2025-07-31 | 4.4900%             |

### Daily Net Asset Value per Share (Series)
| Date       | Net Asset Value per Share   |
|:---|:---|
| 2025-07-01 | 1.0001                      |
|  |  |
| 2025-07-02 | 1.0001                      |
|  |  |
| 2025-07-03 | 0.9999                      |
|  |  |
| 2025-07-07 | 1.0000                      |
|  |  |
| 2025-07-08 | 1.0000                      |
|  |  |
| 2025-07-09 | 1.0000                      |
|  |  |
| 2025-07-10 | 1.0001                      |
|  |  |
| 2025-07-11 | 1.0000                      |
|  |  |
| 2025-07-14 | 1.0000                      |
|  |  |
| 2025-07-15 | 1.0000                      |
|  |  |
| 2025-07-16 | 1.0000                      |
|  |  |
| 2025-07-17 | 1.0000                      |
|  |  |
| 2025-07-18 | 1.0000                      |
|  |  |
| 2025-07-21 | 1.0000                      |
|  |  |
| 2025-07-22 | 1.0000                      |
|  |  |
| 2025-07-23 | 1.0001                      |
|  |  |
| 2025-07-24 | 1.0001                      |
|  |  |
| 2025-07-25 | 1.0000                      |
|  |  |
| 2025-07-28 | 1.0001                      |
|  |  |
| 2025-07-29 | 1.0001                      |
|  |  |
| 2025-07-30 | 1.0001                      |
|  |  |
| 2025-07-31 | 1.0001                      |
|  |  |

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

### Class: Single Class

- **Minimum Initial Investment:** $50000000.00

- **Net Assets of Class:** $10098761542.80

- **Number of Shares Outstanding:** 10098093822.6010

- **Expense Reimbursement/Waiver:** 348169.00

**Daily Net Asset Value per Share (Class)**
| Date       | NAV per Share   |
|:---|:---|
| 2025-07-01 | 1.0001          |
|  |  |
| 2025-07-02 | 1.0001          |
|  |  |
| 2025-07-03 | 0.9999          |
|  |  |
| 2025-07-07 | 1.0000          |
|  |  |
| 2025-07-08 | 1.0000          |
|  |  |
| 2025-07-09 | 1.0000          |
|  |  |
| 2025-07-10 | 1.0001          |
|  |  |
| 2025-07-11 | 1.0000          |
|  |  |
| 2025-07-14 | 1.0000          |
|  |  |
| 2025-07-15 | 1.0000          |
|  |  |
| 2025-07-16 | 1.0000          |
|  |  |
| 2025-07-17 | 1.0000          |
|  |  |
| 2025-07-18 | 1.0000          |
|  |  |
| 2025-07-21 | 1.0000          |
|  |  |
| 2025-07-22 | 1.0000          |
|  |  |
| 2025-07-23 | 1.0001          |
|  |  |
| 2025-07-24 | 1.0001          |
|  |  |
| 2025-07-25 | 1.0000          |
|  |  |
| 2025-07-28 | 1.0001          |
|  |  |
| 2025-07-29 | 1.0001          |
|  |  |
| 2025-07-30 | 1.0001          |
|  |  |
| 2025-07-31 | 1.0001          |
|  |  |

**Daily Shareholder Flows**
| Date       | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| 2025-07-01 | $93779065.32              | $38627324.50            |
| 2025-07-02 | $42735630.46              | $52490752.69            |
| 2025-07-03 | $38796107.31              | $22591677.34            |
| 2025-07-07 | $33367808.19              | $47456618.71            |
| 2025-07-08 | $48562716.15              | $41067125.93            |
| 2025-07-09 | $26491482.49              | $57226452.45            |
| 2025-07-10 | $44997603.98              | $56171267.50            |
| 2025-07-11 | $46922841.61              | $68272416.85            |
| 2025-07-14 | $28423618.05              | $51956326.39            |
| 2025-07-15 | $51889475.79              | $72818367.50            |
| 2025-07-16 | $67897588.55              | $52685226.05            |
| 2025-07-17 | $37656262.27              | $93890782.63            |
| 2025-07-18 | $64414928.30              | $39481545.09            |
| 2025-07-21 | $55225456.64              | $79774787.22            |
| 2025-07-22 | $32998767.39              | $58034293.24            |
| 2025-07-23 | $35871103.74              | $59194402.47            |
| 2025-07-24 | $36419241.75              | $55896234.53            |
| 2025-07-25 | $44165220.96              | $115714216.03           |
| 2025-07-28 | $88755115.40              | $72914005.28            |
| 2025-07-29 | $41407972.59              | $57305445.07            |
| 2025-07-30 | $53966903.46              | $45716595.57            |
| 2025-07-31 | $77071527.50              | $68852012.45            |

**Total Gross Subscriptions (Month):** $1091816437.90

**Total Gross Redemptions (Month):** $1308137875.49

**7-Day Net Yield (Class)**
| Date       | 7-Day Net Yield   |
|:---|:---|
| 2025-07-01 | 4.3600%           |
| 2025-07-02 | 4.3700%           |
| 2025-07-03 | 4.3600%           |
| 2025-07-07 | 4.3600%           |
| 2025-07-08 | 4.3500%           |
| 2025-07-09 | 4.3500%           |
| 2025-07-10 | 4.3400%           |
| 2025-07-11 | 4.3300%           |
| 2025-07-14 | 4.3300%           |
| 2025-07-15 | 4.3300%           |
| 2025-07-16 | 4.3300%           |
| 2025-07-17 | 4.3300%           |
| 2025-07-18 | 4.3400%           |
| 2025-07-21 | 4.3400%           |
| 2025-07-22 | 4.3400%           |
| 2025-07-23 | 4.3300%           |
| 2025-07-24 | 4.3300%           |
| 2025-07-25 | 4.3300%           |
| 2025-07-28 | 4.3400%           |
| 2025-07-29 | 4.3400%           |
| 2025-07-30 | 4.3500%           |
| 2025-07-31 | 4.3500%           |

## Part C: Schedule of Portfolio Securities

### Security 1: Prime CNAV Master Fund

- **C.1 - Title:** Prime CNAV Master Fund
- **C.6 - Investment Category:** Investment Company
- **Identifiers:** C.3 - CUSIP: 927XQC905, C.3 - LEI: 549300K8VKMIOPMVLW91, C.5 - Other ID: 927XQC905
- **C.18 - Value (incl. sponsor support):** $10136353390.00
- **C.18.a - Value (excl. sponsor support):** $10136353390.00
- **C.19 - Percentage of Net Assets:** 100.0000%
- **C.17 - Yield as of Reporting Date:** 0.0000%
- **C.11 - Maturity Date (WAM):** 2025-08-01
- **C.12 - Maturity Date (WAL):** 2025-08-01
- **C.13 - Final Legal Maturity Date:** 2025-08-01
- **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:** 2025-08-07

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

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

**Title of Signing Officer:** Vice President