# EDGAR Filing Document

**Accession Number:** 0000822632
**File Stem:** 0001193125-26-010073
**Filing Date:** 2026-1
**Character Count:** 3285
**Document Hash:** f015bbc1bd4cbfb1076ab4ac84346b94
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-26-010073.hdr.sgml**: 20260112

**ACCESSION NUMBER**: 0001193125-26-010073

**CONFORMED SUBMISSION TYPE**: 497K

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20260112

**DATE AS OF CHANGE**: 20260112

**EFFECTIVENESS DATE**: 20260112

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** WILLIAM BLAIR FUNDS
- **CENTRAL INDEX KEY:** 0000822632

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 497K
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 033-17463
- **FILM NUMBER:** 26525421

**BUSINESS ADDRESS:**
- **STREET 1:** 150 NORTH RIVERSIDE PLAZA
- **CITY:** CHICAGO
- **STATE:** IL
- **ZIP:** 60606
- **BUSINESS PHONE:** 3123648000

**MAIL ADDRESS:**
- **STREET 1:** 150 NORTH RIVERSIDE PLAZA
- **CITY:** CHICAGO
- **STATE:** IL
- **ZIP:** 60606

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** WILLIAM BLAIR MUTUAL FUNDS INC
- **DATE OF NAME CHANGE:** 19960112

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** BLAIR WILLIAM READY RESERVES INC
- **DATE OF NAME CHANGE:** 19920316

## Series and Classes Contracts Data

### William Blair Small-Mid Cap Growth Fund (Series ID: S000008603)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000023542 | Class N      | WSMNX           |
| C000023543 | Class I      | WSMDX           |
| C000211721 | Class R6     | WSMRX           |

**WILLIAM BLAIR FUNDS** 

**William Blair Small-Mid Cap Growth Fund** 

**(the "Fund")** 

Supplement dated January 12, 2026 to the Fund's Summary Prospectus dated May 1, 2025

and the Prospectus dated May 1, 2025, as supplemented

Effective February 1, 2026:

1. The information below replaces similar disclosure in the "Management" section of the Fund's
Summary Prospectus and the "Summary – Management" section of the Prospectus as follows:

**Portfolio Managers.** Daniel Crowe, Ward Sexton and Nicholas Zimmerman, Partners of the Adviser, co-manage the Fund. Mr. Crowe has co-managed the Fund since 2015. Mr. Sexton has co-managed the Fund since 2026. Mr. Zimmerman has co-managed the Fund since 2023.

It is expected that Mr. Crowe will remain a co-portfolio manager of the Fund until December 31, 2026.

2. The biography for Mr. Sexton contained in the Prospectus section entitled "Management of the Funds
– Portfolio Management" is replaced with the following:

Ward Sexton, CFA, a Partner of William Blair Investment Management, LLC, has co-managed the Small Cap Growth Fund since 2016, the Small-Mid Cap Core Fund since its inception in 2019 and the Small-Mid Cap Growth Fund since 2026. In 2001, he joined the Adviser's investment team as a research analyst and covered Resources, Financials, and Consumer companies at various points during his time as an analyst. He joined William Blair in 1999 and worked in the firm's corporate finance group for two years. He has the Chartered Financial Analyst designation and is a member of the CFA Institute and the CFA Society of Chicago. Education: B.S., Finance (with honors), University of Illinois Urbana-Champaign; M.B.A., (high honors), University of Chicago Booth School of Business.

**WILLIAM BLAIR FUNDS** 

150 North Riverside Plaza

Chicago, Illinois 60606

Please retain this supplement for future reference.