# EDGAR Filing Document

**Accession Number:** 0001060517
**File Stem:** 0001145549-25-046120
**Filing Date:** 2025-7
**Character Count:** 13176
**Document Hash:** 66db2942c664f502766f73676a1a76c2
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001145549-25-046120.hdr.sgml**: 20250708

**ACCESSION NUMBER**: 0001145549-25-046120

**CONFORMED SUBMISSION TYPE**: N-MFP3

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20250630

**FILED AS OF DATE**: 20250708

**DATE AS OF CHANGE**: 20250708

**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:** 251110720

**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):** 2025-06-30

**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:** $10352677548.10

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

- **Cash:** $0.00

- **Total Other Assets:** $0.00

- **Total Liabilities:** $37594567.71

- **Net Assets of Series:** $10315082980.39

- **Number of Shares Outstanding (Series):** 10314415260.1910

- **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 (%)   |
|:---|:---|:---|:---|:---|
| 2025-06-02 | $9533304061.18            | $13216900515.89            | 37.6700%                  | 52.2200%                   |
| 2025-06-03 | $10521086106.94           | $13184774220.95            | 41.4300%                  | 51.9200%                   |
| 2025-06-04 | $9735506587.56            | $13187673877.13            | 38.3500%                  | 51.9400%                   |
| 2025-06-05 | $9705916315.06            | $13325151928.96            | 38.1400%                  | 52.3600%                   |
| 2025-06-06 | $10709249182.77           | $13099326340.57            | 42.3100%                  | 51.7500%                   |
| 2025-06-09 | $9964202572.53            | $13291793289.83            | 39.4200%                  | 52.5900%                   |
| 2025-06-10 | $10930059937.97           | $13313840422.77            | 43.2600%                  | 52.6900%                   |
| 2025-06-11 | $10281332167.90           | $13288672525.40            | 40.7300%                  | 52.6500%                   |
| 2025-06-12 | $10151448500.40           | $13089075822.30            | 40.2900%                  | 51.9400%                   |
| 2025-06-13 | $11451426061.08           | $13082819717.78            | 45.3500%                  | 51.8100%                   |
| 2025-06-16 | $10762325386.16           | $12858495157.26            | 43.0100%                  | 51.3900%                   |
| 2025-06-17 | $11025752477.14           | $12878573644.14            | 44.0300%                  | 51.4300%                   |
| 2025-06-18 | $10540885052.97           | $13133262076.47            | 41.9900%                  | 52.3200%                   |
| 2025-06-20 | $10926140414.74           | $12939323856.24            | 43.6400%                  | 51.6900%                   |
| 2025-06-23 | $10955761715.81           | $12689162826.81            | 44.0000%                  | 50.9600%                   |
| 2025-06-24 | $10727134188.34           | $12682047876.74            | 43.1600%                  | 51.0300%                   |
| 2025-06-25 | $10203865640.83           | $12628711473.43            | 41.1400%                  | 50.9200%                   |
| 2025-06-26 | $10322808267.27           | $12781497704.49            | 41.6200%                  | 51.5300%                   |
| 2025-06-27 | $11912462037.70           | $13226584556.05            | 47.8800%                  | 53.1600%                   |
| 2025-06-30 | $11535564455.45           | $13177544016.17            | 46.4600%                  | 53.0700%                   |

### 7-Day Gross Yield
| Date       | 7-Day Gross Yield   |
|:---|:---|
| 2025-06-02 | 4.4900%             |
| 2025-06-03 | 4.4900%             |
| 2025-06-04 | 4.4900%             |
| 2025-06-05 | 4.4800%             |
| 2025-06-06 | 4.4600%             |
| 2025-06-09 | 4.4600%             |
| 2025-06-10 | 4.4600%             |
| 2025-06-11 | 4.4500%             |
| 2025-06-12 | 4.4500%             |
| 2025-06-13 | 4.4500%             |
| 2025-06-16 | 4.4500%             |
| 2025-06-17 | 4.4600%             |
| 2025-06-18 | 4.4600%             |
| 2025-06-20 | 4.4600%             |
| 2025-06-23 | 4.4600%             |
| 2025-06-24 | 4.4600%             |
| 2025-06-25 | 4.4600%             |
| 2025-06-26 | 4.4700%             |
| 2025-06-27 | 4.4900%             |
| 2025-06-30 | 4.5000%             |

### Daily Net Asset Value per Share (Series)
| Date       | Net Asset Value per Share   |
|:---|:---|
| 2025-06-02 | 1.0000                      |
|  |  |
| 2025-06-03 | 1.0000                      |
|  |  |
| 2025-06-04 | 1.0000                      |
|  |  |
| 2025-06-05 | 1.0000                      |
|  |  |
| 2025-06-06 | 0.9999                      |
|  |  |
| 2025-06-09 | 1.0000                      |
|  |  |
| 2025-06-10 | 1.0000                      |
|  |  |
| 2025-06-11 | 1.0000                      |
|  |  |
| 2025-06-12 | 1.0000                      |
|  |  |
| 2025-06-13 | 1.0000                      |
|  |  |
| 2025-06-16 | 1.0000                      |
|  |  |
| 2025-06-17 | 1.0000                      |
|  |  |
| 2025-06-18 | 1.0000                      |
|  |  |
| 2025-06-20 | 1.0000                      |
|  |  |
| 2025-06-23 | 1.0000                      |
|  |  |
| 2025-06-24 | 1.0000                      |
|  |  |
| 2025-06-25 | 1.0001                      |
|  |  |
| 2025-06-26 | 1.0001                      |
|  |  |
| 2025-06-27 | 1.0000                      |
|  |  |
| 2025-06-30 | 1.0001                      |
|  |  |

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

### Class: Single Class

- **Minimum Initial Investment:** $50000000.00

- **Net Assets of Class:** $10315082980.39

- **Number of Shares Outstanding:** 10314415260.1910

- **Expense Reimbursement/Waiver:** 333016.00

**Daily Net Asset Value per Share (Class)**
| Date       | NAV per Share   |
|:---|:---|
| 2025-06-02 | 1.0000          |
|  |  |
| 2025-06-03 | 1.0000          |
|  |  |
| 2025-06-04 | 1.0000          |
|  |  |
| 2025-06-05 | 1.0000          |
|  |  |
| 2025-06-06 | 0.9999          |
|  |  |
| 2025-06-09 | 1.0000          |
|  |  |
| 2025-06-10 | 1.0000          |
|  |  |
| 2025-06-11 | 1.0000          |
|  |  |
| 2025-06-12 | 1.0000          |
|  |  |
| 2025-06-13 | 1.0000          |
|  |  |
| 2025-06-16 | 1.0000          |
|  |  |
| 2025-06-17 | 1.0000          |
|  |  |
| 2025-06-18 | 1.0000          |
|  |  |
| 2025-06-20 | 1.0000          |
|  |  |
| 2025-06-23 | 1.0000          |
|  |  |
| 2025-06-24 | 1.0000          |
|  |  |
| 2025-06-25 | 1.0001          |
|  |  |
| 2025-06-26 | 1.0001          |
|  |  |
| 2025-06-27 | 1.0000          |
|  |  |
| 2025-06-30 | 1.0001          |
|  |  |

**Daily Shareholder Flows**
| Date       | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| 2025-06-02 | $118107627.51             | $55262170.24            |
| 2025-06-03 | $68983631.03              | $78454526.30            |
| 2025-06-04 | $45144408.33              | $46102292.47            |
| 2025-06-05 | $36383192.26              | $79399554.28            |
| 2025-06-06 | $35442534.58              | $36421553.89            |
| 2025-06-09 | $30381069.66              | $49040725.98            |
| 2025-06-10 | $42279733.13              | $47935467.77            |
| 2025-06-11 | $37074573.26              | $50268331.49            |
| 2025-06-12 | $31022425.23              | $94470965.98            |
| 2025-06-13 | $56041197.51              | $58508360.94            |
| 2025-06-16 | $47870587.60              | $131782215.40           |
| 2025-06-17 | $57056964.99              | $58321082.46            |
| 2025-06-18 | $48335086.48              | $63874620.32            |
| 2025-06-20 | $51501438.56              | $80226517.24            |
| 2025-06-23 | $43061221.03              | $94817276.77            |
| 2025-06-24 | $54317014.49              | $70597561.07            |
| 2025-06-25 | $34227531.56              | $62668247.92            |
| 2025-06-26 | $72441545.38              | $61296077.88            |
| 2025-06-27 | $125333723.00             | $73394726.75            |
| 2025-06-30 | $63502230.43              | $104456706.93           |

**Total Gross Subscriptions (Month):** $1098507736.02

**Total Gross Redemptions (Month):** $1397298982.08

**7-Day Net Yield (Class)**
| Date       | 7-Day Net Yield   |
|:---|:---|
| 2025-06-02 | 4.3400%           |
| 2025-06-03 | 4.3500%           |
| 2025-06-04 | 4.3500%           |
| 2025-06-05 | 4.3400%           |
| 2025-06-06 | 4.3200%           |
| 2025-06-09 | 4.3200%           |
| 2025-06-10 | 4.3200%           |
| 2025-06-11 | 4.3100%           |
| 2025-06-12 | 4.3100%           |
| 2025-06-13 | 4.3100%           |
| 2025-06-16 | 4.3100%           |
| 2025-06-17 | 4.3100%           |
| 2025-06-18 | 4.3200%           |
| 2025-06-20 | 4.3200%           |
| 2025-06-23 | 4.3200%           |
| 2025-06-24 | 4.3200%           |
| 2025-06-25 | 4.3200%           |
| 2025-06-26 | 4.3300%           |
| 2025-06-27 | 4.3500%           |
| 2025-06-30 | 4.3600%           |

## 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):** $10352677548.10
- **C.18.a - Value (excl. sponsor support):** $10352677548.10
- **C.19 - Percentage of Net Assets:** 100.0000%
- **C.17 - Yield as of Reporting Date:** 0.0000%
- **C.11 - Maturity Date (WAM):** 2025-07-01
- **C.12 - Maturity Date (WAL):** 2025-07-01
- **C.13 - Final Legal Maturity Date:** 2025-07-01
- **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:** 2025-07-08

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

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

**Title of Signing Officer:** Vice President