# EDGAR Filing Document

**Accession Number:** 0000822632
**File Stem:** 0001193125-25-205671
**Filing Date:** 2025-9
**Character Count:** 25438
**Document Hash:** 7dfde59ece7b533f4e40f8db26ef386c
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-25-205671.hdr.sgml**: 20250917

**ACCESSION NUMBER**: 0001193125-25-205671

**CONFORMED SUBMISSION TYPE**: 497

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20250917

**DATE AS OF CHANGE**: 20250917

**EFFECTIVENESS DATE**: 20250917

**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:** 497
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 033-17463
- **FILM NUMBER:** 251319051

**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 Growth Fund (Series ID: S000008594)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class N    | WBGSX         | C000023523 |
| Class I    | BGFIX         | C000023524 |
| Class R6   | BGFRX         | C000211716 |

---

### William Blair International Small Cap Growth Fund (Series ID: S000008595)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class N    | WISNX         | C000023525 |
| Class I    | WISIX         | C000023526 |
| Class R6   | WIISX         | C000023527 |

---

### William Blair Emerging Markets Growth Fund (Series ID: S000008596)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class N    | WBENX         | C000023528 |
| Class I    | WBEIX         | C000023529 |
| Class R6   | BIEMX         | C000023530 |

---

### William Blair Small Cap Value Fund (Series ID: S000008597)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class N    | WBVNX         | C000023531 |
| Class I    | ICSCX         | C000023532 |
| Class R6   | WBVRX         | C000211717 |

---

### William Blair Large Cap Growth Fund (Series ID: S000008601)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class N    | LCGNX         | C000023538 |
| Class I    | LCGFX         | C000023539 |
| Class R6   | LCGJX         | C000211719 |

---

### William Blair Small Cap Growth Fund (Series ID: S000008602)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class N    | WBSNX         | C000023540 |
| Class I    | WBSIX         | C000023541 |
| Class R6   | WBSRX         | C000211720 |

---

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

---

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

---

### William Blair International Growth Fund (Series ID: S000008604)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class N    | WBIGX         | C000023544 |
| Class I    | BIGIX         | C000023545 |
| Class R6   | WBIRX         | C000211722 |

---

### William Blair Institutional International Growth Fund (Series ID: S000008605)

---

|  |  |  |
|:---|:---|:---|
| Class Name          | Ticker Symbol | Class ID   |
| Institutional Class | WBIIX         | C000023546 |

---

### William Blair Global Leaders Fund (Series ID: S000019315)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class N    | WGGNX         | C000053607 |
| Class I    | WGFIX         | C000053608 |
| Class R6   | BGGIX         | C000053609 |

---

### William Blair Emerging Markets Leaders Fund (Series ID: S000021052)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class I    | WBELX         | C000059867 |
| Class R6   | WELIX         | C000059868 |
| Class N    | WELNX         | C000088850 |

---

### William Blair Emerging Markets Small Cap Growth Fund (Series ID: S000034349)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class I    | BESIX         | C000105753 |
| Class N    | WESNX         | C000105754 |
| Class R6   | WESJX         | C000105755 |

---

### William Blair International Leaders Fund (Series ID: S000037763)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class N    | WILNX         | C000116468 |
| Class I    | WILIX         | C000116469 |
| Class R6   | WILJX         | C000116470 |

---

### William Blair Small-Mid Cap Core Fund (Series ID: S000066499)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class I    | WBCIX         | C000214491 |
| Class R6   | WBCRX         | C000214492 |

---

### William Blair Emerging Markets Debt Fund (Series ID: S000069167)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class R6   | WEDRX         | C000221008 |
| Class I    | WEDIX         | C000221009 |

---

### William Blair China Growth Fund (Series ID: S000072753)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class I    | WICGX         | C000229252 |
| Class R6   | WRCGX         | C000229253 |

---

### William Blair Emerging Markets ex China Growth Fund (Series ID: S000075390)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class I    | WXCIX         | C000234384 |
| Class R6   | WXCRX         | C000234385 |

---

### William Blair Mid Cap Value Fund (Series ID: S000075391)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class I    | WVMIX         | C000234386 |
| Class R6   | WVMRX         | C000234387 |

---

### William Blair Small-Mid Cap Value Fund (Series ID: S000080810)

---

|  |  |  |
|:---|:---|:---|
| Class Name | Ticker Symbol | Class ID   |
| Class I    | ISMVX         | C000243363 |
| Class R6   | RSMVX         | C000243364 |

---

## Series and Classes Contracts Data

### William Blair Growth Fund (Series ID: S000008594)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000023523 | Class N      | WBGSX           |
| C000023524 | Class I      | BGFIX           |
| C000211716 | Class R6     | BGFRX           |

### William Blair International Small Cap Growth Fund (Series ID: S000008595)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000023525 | Class N      | WISNX           |
| C000023526 | Class I      | WISIX           |
| C000023527 | Class R6     | WIISX           |

### William Blair Emerging Markets Growth Fund (Series ID: S000008596)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000023528 | Class N      | WBENX           |
| C000023529 | Class I      | WBEIX           |
| C000023530 | Class R6     | BIEMX           |

### William Blair Small Cap Value Fund (Series ID: S000008597)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000023531 | Class N      | WBVNX           |
| C000023532 | Class I      | ICSCX           |
| C000211717 | Class R6     | WBVRX           |

### William Blair Large Cap Growth Fund (Series ID: S000008601)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000023538 | Class N      | LCGNX           |
| C000023539 | Class I      | LCGFX           |
| C000211719 | Class R6     | LCGJX           |

### William Blair Small Cap Growth Fund (Series ID: S000008602)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000023540 | Class N      | WBSNX           |
| C000023541 | Class I      | WBSIX           |
| C000211720 | Class R6     | WBSRX           |

### 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 International Growth Fund (Series ID: S000008604)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000023544 | Class N      | WBIGX           |
| C000023545 | Class I      | BIGIX           |
| C000211722 | Class R6     | WBIRX           |

### William Blair Institutional International Growth Fund (Series ID: S000008605)

| Class ID   | Class Name          | Ticker Symbol   |
|:---|:---|:---|
| C000023546 | Institutional Class | WBIIX           |

### William Blair Global Leaders Fund (Series ID: S000019315)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000053607 | Class N      | WGGNX           |
| C000053608 | Class I      | WGFIX           |
| C000053609 | Class R6     | BGGIX           |

### William Blair Emerging Markets Leaders Fund (Series ID: S000021052)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000059867 | Class I      | WBELX           |
| C000059868 | Class R6     | WELIX           |
| C000088850 | Class N      | WELNX           |

### William Blair Emerging Markets Small Cap Growth Fund (Series ID: S000034349)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000105753 | Class I      | BESIX           |
| C000105754 | Class N      | WESNX           |
| C000105755 | Class R6     | WESJX           |

### William Blair International Leaders Fund (Series ID: S000037763)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000116468 | Class N      | WILNX           |
| C000116469 | Class I      | WILIX           |
| C000116470 | Class R6     | WILJX           |

### William Blair Small-Mid Cap Core Fund (Series ID: S000066499)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000214491 | Class I      | WBCIX           |
| C000214492 | Class R6     | WBCRX           |

### William Blair Emerging Markets Debt Fund (Series ID: S000069167)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000221008 | Class R6     | WEDRX           |
| C000221009 | Class I      | WEDIX           |

### William Blair China Growth Fund (Series ID: S000072753)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000229252 | Class I      | WICGX           |
| C000229253 | Class R6     | WRCGX           |

### William Blair Emerging Markets ex China Growth Fund (Series ID: S000075390)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000234384 | Class I      | WXCIX           |
| C000234385 | Class R6     | WXCRX           |

### William Blair Mid Cap Value Fund (Series ID: S000075391)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000234386 | Class I      | WVMIX           |
| C000234387 | Class R6     | WVMRX           |

### William Blair Small-Mid Cap Value Fund (Series ID: S000080810)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000243363 | Class I      | ISMVX           |
| C000243364 | Class R6     | RSMVX           |

**WILLIAM BLAIR FUNDS** 

**Supplement dated September 17, 2025 to the Statement of Additional Information dated May 1, 2025** 

*Effective immediately, the information below replaces similar disclosure in the Statement of Additional Information ("SAI").* 

**Interested Trustee** 

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
| **Name and Year of Birth** | **Position(s)<br>Held with<br>Trust** | **Term of<br>Office<br>and<br>Length of<br>Time Served** | **Principal<br>Occupation(s)<br>During Past 5<br>Years** | **Number of<br>Portfolios in<br>Trust<br>Complex<br>Overseen by<br>Trustee** | **Other<br>Directorships<br>Held by<br>Trustee\*** |
|  Cissie Citardi,<br> 1975<sup>(2)</sup> | Trustee | Since 2021 | General Counsel (since<br>2021), Deputy General<br>Counsel (May 2020 to<br>December 2020) and<br>Partner, William Blair;<br>formerly, General<br>Counsel, PineBridge<br>Investments (2016 to<br>2020) | 19 | Director,<br> William Blair<br>SICAV |

---

† William Blair Investment Management, LLC and William Blair & Company, L.L.C. are collectively referred
to in this section as "William Blair," each of which is a wholly owned subsidiary of WBC Holdings, L.P., which is wholly owned by certain William Blair employees (employee owners are referred to as 'partners').

\* Includes directorships of public companies and other registered investment companies held during the past five years.

(1) Each Trustee serves until the election and qualification of a successor, or until death, resignation or
retirement, or removal as provided in the Trust's Declaration of Trust.

(2) Ms. Citardi is an interested person of the Trust because she is a partner of William Blair.

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
| **Non-Interested Trustees** | **Non-Interested Trustees** | **Non-Interested Trustees** | **Non-Interested Trustees** | **Non-Interested Trustees** | **Non-Interested Trustees** |
| **Name and Year of Birth** | **Position(s)<br>Held with Trust** | **Term of<br>Office<br>and<br>Length of<br>Time Served** | **Principal<br>Occupation(s)<br>During Past 5<br>Years** | **Number of<br>Portfolios in<br>Trust<br>Complex<br>Overseen by<br>Trustee** | **Other<br>Directorships<br>Held by<br>Trustee\*** |
|  Vann A. Avedisian,<br> 1964 | Trustee | Since 2012 | Co-founder and Partner,<br>Newbond Holdings (real<br>estate operations) (since<br>2021); formerly, Principal,<br>Highgate Holdings (hotel<br>investments) (2009 to<br>2021); co-founder and<br>Managing Director, Oxford<br>Capital Partners Inc. (1994<br>to 2006) | 19 | Potbelly Sandwich Works (2001 to 2015 and since 2021) |

---

------

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
| **Non-Interested Trustees** | **Non-Interested Trustees** | **Non-Interested Trustees** | **Non-Interested Trustees** | **Non-Interested Trustees** | **Non-Interested Trustees** |
| **Name and Year of Birth** | **Position(s)<br>Held with Trust** | **Term of<br>Office<br>and<br>Length of<br>Time Served** | **Principal<br>Occupation(s)<br>During Past 5<br>Years** | **Number of<br>Portfolios in<br>Trust<br>Complex<br>Overseen by<br>Trustee** | **Other<br>Directorships<br>Held by<br>Trustee\*** |
|  Kathleen T. Barr,<br> 1955 | Chair of the Board | Trustee since 2013 and Chair of the Board since 2025 | Retired; Chair Emeritus,<br>Independent Directors<br>Council (since 2022);<br>formerly, Chairman of the<br>Governing Council,<br>Independent Directors<br>Council (2020 to 2022);<br>formerly, President,<br>Productive Capital<br>Management, Inc.<br>(registered investment<br>adviser to public entities)<br>and Owner, KT Barr<br>Consulting, LLC (mutual<br>fund and investment<br>management consulting)<br>(2010 to 2013); prior<br>thereto, Chief<br>Administrative Officer,<br>Senior Vice President and<br>Senior Managing Director<br>of Allegiant Asset<br>Management Company<br>(merged with PNC Capital<br>Advisors, LLC in 2009)<br>(2004 to 2010) | 19 | Muzinich BDC, Inc. (since 2019) and Muzinich Corporate Lending Income Fund, Inc. (since 2023); Board of Governors, Investment Company Institute (since 2019); Professionally Managed Portfolios (since 2018) |
|  Michelle E. Borré Massick,<br> 1967 | Trustee | Trustee since 2024 | Portfolio Advisor, Tishman<br>Capital Partners (RIA)<br>(since 2024); Consultant,<br>Great Rock Advisors LLC<br>(investment management<br>consulting) (since 2022);<br>formerly, Founder,<br>Financial Education<br>Platform (2020 to 2022);<br>formerly, Senior Portfolio<br>Manager, Head of<br>Fundamental Alternative<br>Strategies, Invesco (2019<br>to 2020); formerly, Senior<br>Portfolio Manager, Senior<br>Vice President,<br>OppenheimerFunds (2003<br>to 2019) | 19 | Rock the Street, Wall Street (since 2022) |

---

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---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
| **Non-Interested Trustees** | **Non-Interested Trustees** | **Non-Interested Trustees** | **Non-Interested Trustees** | **Non-Interested Trustees** | **Non-Interested Trustees** |
| **Name and Year of Birth** | **Position(s)<br>Held with Trust** | **Term of<br>Office<br>and<br>Length of<br>Time Served** | **Principal<br>Occupation(s)<br>During Past 5<br>Years** | **Number of<br>Portfolios in<br>Trust<br>Complex<br>Overseen by<br>Trustee** | **Other<br>Directorships<br>Held by<br>Trustee\*** |
|  Daniel N. Leib,<br> 1966<sup>(2)</sup> | Trustee and Chair, Nominating and Governance Committee | Trustee since 2016 and Chair of Nominating and Governance Committee since 2023 | Chief Executive Officer,<br>Donnelley Financial<br>Solutions, Inc. (since<br>2016); formerly, Executive<br>Vice President and Chief<br>Financial Officer (2011 to<br>2016) and Group Chief<br>Financial Officer (2009 to<br>2011), R. R. Donnelley &<br>Sons Company | 19 | Donnelley Financial Solutions, Inc. (since 2016) |
|  Dorri C. McWhorter,<br> 1973 | Trustee and Chair, Compliance Committee | Trustee since 2019 and Chair of Compliance Committee since 2021 | President and Chief<br>Executive Officer, The<br>Executives' Club of<br>Chicago (since 2025);<br>formerly, President and<br>Chief Executive Officer,<br>YMCA of Metropolitan<br>Chicago (2021 to 2025);<br>Chief Executive Officer,<br>YWCA Metropolitan<br>Chicago (2013 to 2021);<br>Partner, Crowe LLP (2008<br>to 2013) | 19 | NexPoint Funds (open-end funds, closed-end funds and business development company (since 2022); Highland Funds (since 2022); Skyway Concession Company, LLC (since 2018); Green Thumb Industries, Inc. (2022); Lifeway Foods, Inc. (since 2020); LanzaTech Global, Inc. (since 2023) |
|  Steven R. Zenz,<br> 1954 | Trustee and Chair, Audit Committee | Trustee since 2018 and Chair of Audit Committee since 2021 | Consultant, Steven R. Zenz<br>Consulting LLC (merger<br>and acquisition<br>transactions and SEC<br>reporting and filings)<br>(since 2011); formerly,<br>Partner, KPMG LLP<br>(1987 to 2010)<sup>(3)</sup> | 19 | Engine Media Holdings, Inc. (media group supporting esports, news streaming and gaming) (2020 to 2021); Frankly Inc. (technology products/services for media industry) (2016 to 2020) |

---

\* Includes directorships of public companies and other registered investment companies held during the past five years.

(1) Each Trustee serves until the election and qualification of a successor, or until death, resignation or
retirement, or removal as provided in the Trust's Declaration of Trust. Retirement for Independent Trustees occurs no later than at the

------

conclusion of the calendar year that occurs after the earlier of (a) the Independent Trustee's 75th birthday or (b) the 17th anniversary of the date that the Independent Trustee became a member of the Board of Trustees.

(2) The Trust and William Blair use Donnelley Financial Solutions, Inc. ("DFS") for financial printing
and other services. DFS is a public company. The Trust and William Blair in the aggregate paid DFS approximately $230,000 and $294,000 in 2023 and 2024, respectively, for the services provided. DFS's revenue was approximately $797 million in
2023 and $782 million in 2024. Mr. Leib, as the Chief Executive Officer of DFS, is not directly involved in any of the services provided to the Trust or William Blair and his compensation is not materially affected by the fees DFS receives from
the Trust and William Blair.

(3) The Trust engages KPMG to provide foreign tax services in Taiwan. KPMG does not provide audit or audit-related
services to the Trust. Mr. Zenz is a former partner of KPMG and receives pension/retirement funds from KPMG.

---

| | | | |
|:---|:---|:---|:---|
| **Officers** | **Officers** | **Officers** | **Officers** |
| **Name and Year of Birth** | **Position(s) Held with Trust** | **Term of Office and**<br> **Length of Time Served <sup>(1)</sup>** | **Principal Occupation(s)**<br>**During Past 5 Years** |
|  Lisa D. Rusch, 1970 | President<br> Senior Vice President | Since 2025<br> 2020-2025 | Partner, William Blair<br>(since 2020);<br>formerly, Associate,<br>William Blair |
| Alaina Anderson, CFA, 1975 | Senior Vice President | Since 2021 | Partner, William Blair |
|  Marcelo Assalin, CFA, 1973 | Senior Vice President | Since 2020 | Partner, William Blair<br>(since 2022);<br>formerly, Associate,<br>William Blair<br>(2020-2022); NN<br>Investment Partners<br>(formerly, ING<br>Investment<br>Management)<br>(2013-2020) |
|  Paul Birchenough, 1982 | Senior Vice President Vice President | Since 2025<br> 2024-2025 | Partner, William Blair<br>(since 2025);<br>formerly, Associate,<br>William Blair<br>(2024-2025);<br>formerly, Newton<br>Investment<br>Management<br>(2020-2024); AXA<br>Investment Managers<br>(2011-2020) |
|  Daniel Crowe, CFA, 1972 | Senior Vice President | Since 2016 | Partner, William Blair |
| Robert J. Duwa, CFA, 1967 | Senior Vice President | Since 2019 | Partner, William Blair |
| Simon Fennell, 1969 | Senior Vice President | Since 2013 | Partner, William Blair |
| David C. Fording, CFA, 1967 | Senior Vice President | Since 2006 | Partner, William Blair |
| James S. Golan, CFA, 1961 | Senior Vice President | Since 2005 | Partner, William Blair |

---

------

---

| | | | |
|:---|:---|:---|:---|
| **Name and Year of Birth** | **Position(s) Held with Trust** | **Term of Office and**<br> **Length of Time Served <sup>(1)</sup>** | **Principal Occupation(s)**<br>**During Past 5 Years** |
| William V. Heaphy, CFA, 1967 | Senior Vice President | Since 2021 | Associate, William<br>Blair (since 2021);<br>formerly, Principal,<br>Investment<br>Counselors of<br>Maryland, LLC<br>(1994-2021) |
| Kenneth J. McAtamney, 1966 | Senior Vice President | Since 2008 | Partner, William Blair |
| Todd M. McClone, CFA, 1968 | Senior Vice President | Since 2005 | Partner, William Blair |
| Casey K. Preyss, 1976 | Senior Vice President | Since 2015 | Partner, William Blair |
| David P. Ricci, CFA, 1958 | Senior Vice President | Since 2006 | Partner, William Blair |
| Marco Ruijer, CFA, 1975 | Senior Vice President Vice President | Since 2025<br> 2020-2025 | Partner, William Blair<br>(since 2025);<br>formerly, Associate,<br>William Blair<br>(2020-2025);<br>formerly, NN<br>Investment Partners<br>(formerly, ING<br>Investment<br>Management)<br>(2013-2020) |
| Hugo Scott-Gall, 1971 | Senior Vice President | Since 2021 | Partner, William Blair |
| Ward D. Sexton, CFA, 1974 | Senior Vice President | Since 2016 | Partner, William Blair |
| Andrew Siepker, CFA, 1981 | Senior Vice President | Since 2022 | Partner, William Blair |
| Ian Smith, 1978 | Senior Vice President Vice President | Since 2025<br> 2024-2025 | Partner, William Blair<br>(since 2025);<br>formerly, Associate,<br>William Blair (since<br>2024-2025);<br>formerly, Newton<br>Investment Managers<br>(2020-2024);<br>formerly, AXA<br>Investment Managers<br>(2012-2020) |
| Mark C. Thompson, CFA, 1976 | Senior Vice President | Since 2020 | Partner, William Blair |
| Vivian Lin Thurston, CFA, 1972 | Senior Vice President | Since 2021 | Partner, William Blair |

---

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| | | | |
|:---|:---|:---|:---|
| **Name and Year of Birth** | **Position(s) Held with Trust** | **Term of Office and**<br> **Length of Time Served <sup>(1)</sup>** | **Principal Occupation(s)**<br>**During Past 5 Years** |
| Dan Zelazny, 1971 | Senior Vice President | Since 2019 | Partner, William Blair<br>(since 2024);<br>formerly, Associate,<br>William Blair<br>(2019-2024) |
| Nicholas Zimmerman, CFA, 1980 | Senior Vice President | Since 2023 | Partner, William Blair<br>(since 2022);<br>formerly, Associate,<br>William Blair |
| Matthew Fleming, CFA, 1973 | Vice President | Since 2022 | Associate, William<br>Blair (since 2021);<br>formerly, Investment<br>Counselors of<br>Maryland, LLC<br>(2008-2021) |
| Jared Lou, CFA, 1983 | Vice President | Since 2024 | Associate, William<br>Blair (since 2020);<br>formerly, NN<br>Investment Partners<br>(2016-2020) |
| Arun Sharma, 1980 | Vice President | Since 2025 | Associate, William<br>Blair (since 2025);<br>formerly, Cohen &<br>Steers (2019-2025) |
| E. Laura Simsic, 1975 | Chief Compliance Officer and Assistant Secretary | Since 2025 | Associate, William<br>Blair |
| Daniel Carey, 1977 | Chief Legal Officer and Assistant Secretary | Since 2023 | Associate, William<br>Blair |
| John M. Raczek, 1970 | Treasurer<br> Assistant Treasurer | Since 2019<br> 2010-2019 | Associate, William<br>Blair |
| Andrew T. Pfau, 1970 | Secretary | Since 2009 | Associate, William<br>Blair |
| David M. Cihak, 1982 | Assistant Treasurer | Since 2019 | Associate, William<br>Blair |

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(1) The Trust's Officers, except the Chief Compliance Officer, are elected annually by the Board of Trustees.
The Trust's Chief Compliance Officer is designated by the Board of Trustees and may only be removed by action of the Board of Trustees, including a majority of Independent Trustees. Length of Time Served for all Officers indicates the year the
individual became an Officer of the Trust.

*Corresponding changes are also made in other sections of the SAI.* 

**WILLIAM BLAIR FUNDS** 

150 North Riverside Plaza

Chicago, Illinois 60606

Please retain this supplement with your Statement of Additional Information for future reference.