# EDGAR Filing Document

**Accession Number:** 0000885732
**File Stem:** 0001999371-25-017949
**Filing Date:** 2025-11
**Character Count:** 3835
**Document Hash:** b978d85521b4cd812c1d2dc752abb61e
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001999371-25-017949.hdr.sgml**: 20251117

**ACCESSION NUMBER**: 0001999371-25-017949

**CONFORMED SUBMISSION TYPE**: 425

**PUBLIC DOCUMENT COUNT**: 6

**FILED AS OF DATE**: 20251117

**DATE AS OF CHANGE**: 20251114

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** NUVEEN CALIFORNIA SELECT TAX FREE INCOME PORTFOLIO
- **CENTRAL INDEX KEY:** 0000885732

**ORGANIZATION NAME:**
- **EIN:** 363828111
- **STATE OF INCORPORATION:** MA

**FILING VALUES:**
- **FORM TYPE:** 425
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 811-06623
- **FILM NUMBER:** 251488881

**BUSINESS ADDRESS:**
- **STREET 1:** 333 W WACKER DR
- **CITY:** CHICAGO
- **STATE:** IL
- **ZIP:** 60606
- **BUSINESS PHONE:** 3129178200

**MAIL ADDRESS:**
- **STREET 1:** 333 W WACKER DRIVE
- **CITY:** CHICAGO
- **STATE:** IL
- **ZIP:** 60606

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** NUVEEN INSURED CALIFORNIA SELECT TAX FREE INCOME PORTFOLIO
- **DATE OF NAME CHANGE:** 19920929

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** NUVEEN CALIFORNIA SELECT TAX FREE INCOME PORTFOLIO
- **DATE OF NAME CHANGE:** 19600201
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** NUVEEN SELECT TAX FREE INCOME PORTFOLIO
- **CENTRAL INDEX KEY:** 0000883618

**ORGANIZATION NAME:**
- **EIN:** 363806843
- **FISCAL YEAR END:** 0331

**FILING VALUES:**
- **FORM TYPE:** 425

**BUSINESS ADDRESS:**
- **STREET 1:** 333 W WACKER DR
- **CITY:** CHICAGO
- **STATE:** IL
- **ZIP:** 60606
- **BUSINESS PHONE:** 3129178200

**MAIL ADDRESS:**
- **STREET 1:** 333 W WACKER DR
- **CITY:** CHICAGO
- **STATE:** IL
- **ZIP:** 60606

---

| | |
|:---|:---|
| ![](nxc425001.jpg) | Filed by Nuveen Select Tax-Free Income Portfolio<br> (Commission File No. 333-288619)<br> pursuant to Rule 425 under the Securities Act of 1933, as<br> amended, and deemed filed pursuant to Rule 14a-6 under<br> the Securities Exchange Act of 1934, as amended<br> Subject Company: Nuveen California Select Tax-Free Income Portfolio<br> (Commission File No. 811-06623) |

---

**Nuveen California Select Tax-Free Income Portfolio (NXC)**

**Nuveen Select Tax-Free Income Portfolio (NXP)**

**ANNUAL MEETING OF SHAREHOLDERS**

**IMPORTANT SHAREHOLDER INFORMATION**

**Please vote promptly**

**VOTING IS QUICK AND EASY**

Dear Shareholder:

We recently sent you proxy materials concerning important proposals regarding your investment, which were considered at the Annual Meeting of Shareholders on November 14, 2025. The meeting has adjourned until December 18, 2025 to allow shareholders more time to vote. This letter was sent to you because you held shares on the record date and we have not received your vote.

**Your vote is critical to this process. Please vote as soon as possible.** 

Thank you for your prompt attention to this matter. If you have already voted, we appreciate your participation.

*Mark L. Winget*

*Vice President and Secretary*

*The Nuveen Closed-End Funds*

---

| | |
|:---|:---|
| &nbsp;&nbsp;**Vote by one of these four options:** | &nbsp;&nbsp;**Vote by one of these four options:** |
| &nbsp;&nbsp;![](nxc425002.jpg) | &nbsp;&nbsp;![](nxc425003.jpg) |
| &nbsp;&nbsp;**Vote Online**<br> Visit the website noted on the enclosed proxy card and follow the instructions | &nbsp;&nbsp;**Vote by Mail**<br> Mail your signed proxy card(s) in the postage-paid envelope |
| &nbsp;&nbsp;![](nxc425004.jpg) | &nbsp;&nbsp;![](nxc425005.jpg) |
| &nbsp;&nbsp;**Vote by Phone**<br>Call the toll-free number printed on the enclosed proxy card and follow the automated instructions. Available 7 days a week 24 hours a day. | &nbsp;&nbsp;**Speak with a Proxy<br> Specialist**<br> Call 1-877-325-6510 with any questions. Specialists can assist with voting. Available Mon-Fri from 9 a.m. – 11 p.m. ET and Sat from noon – 6 p.m. ET |

---