# EDGAR Filing Document

**Accession Number:** 0000012518
**File Stem:** 0000012518-26-000002
**Filing Date:** 2026-2
**Character Count:** 2827
**Document Hash:** c5595c62af6c31602f7ad0e2fc6aab9e
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000012518-26-000002.hdr.sgml**: 20260226

**ACCESSION NUMBER**: 0000012518-26-000002

**CONFORMED SUBMISSION TYPE**: X-17A-5

**PUBLIC DOCUMENT COUNT**: 2

**CONFORMED PERIOD OF REPORT**: 20251231

**FILED AS OF DATE**: 20260226

**DATE AS OF CHANGE**: 20260226

**EFFECTIVENESS DATE**: 20260226

**PERIOD START**: 20250101

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** WILLIAM BLAIR & COMPANY L.L.C.
- **CENTRAL INDEX KEY:** 0000012518

**ORGANIZATION NAME:**
- **EIN:** 362214610
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** X-17A-5
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 008-02698
- **FILM NUMBER:** 26690705

**BUSINESS ADDRESS:**
- **STREET 1:** THE WILLIAM BLAIR BUILDING
- **STREET 2:** 150 NORTH RIVERSIDE
- **CITY:** CHICAGO
- **STATE:** IL
- **ZIP:** 60606-1594
- **BUSINESS PHONE:** 312-364-8991

**MAIL ADDRESS:**
- **STREET 1:** THE WILLIAM BLAIR BUILDING
- **STREET 2:** 150 NORTH RIVERSIDE
- **CITY:** CHICAGO
- **STATE:** IL
- **ZIP:** 60606-1594

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** WILLIAM BLAIR & Co L.L.C.
- **DATE OF NAME CHANGE:** 20250429

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** WILLIAM BLAIR & COMPANY L.L.C.
- **DATE OF NAME CHANGE:** 20020129

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** WILLIAM BLAIR & CO LLC                                  /BD
- **DATE OF NAME CHANGE:** 20020129

### Attached PDF Documents

**Attachment 1:** `WBC2025CSOFCONLY-A.pdf`

_No text found in this document._

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## FORM X-17A-5

### ANNUAL AUDITED REPORT

### Filer Information

**Filer CIK:** 0000012518

**Filer CCC:** XXXXXXXX

**Is this a LIVE or TEST filing?:** LIVE

**Would you like a Return Copy?:** Yes

### Submission Information

**Report Period Begin Date:** 01-01-2025

**Report Period End Date:** 12-31-2025

**Type of Registrant:** Broker-dealer

**Any material weaknesses identified?:** No

### Registrant Identification

**Name of Broker-Dealer:** WILLIAM BLAIR & COMPANY L.L.C.

**Business Address:** THE WILLIAM BLAIR BUILDING, 150 NORTH RIVERSIDE, CHICAGO, IL, 60606-1594

**Contact Person:** Brent Whitford

**Contact Phone:** 3123648978

### Independent Public Accountant Identification

**Accountant Name:** PricewaterhouseCoopers LLP

**Accountant Address:** 1 N Wacker Drive, Chicago, IL, 60606

**Accountant Type:** Certified Public Accountant

### OATH OR AFFIRMATION

I, **Michael Trimberger**, swear (or affirm) that, to the best of my knowledge and belief, the accompanying financial statements and supporting schedules pertaining to the firm of **WILLIAM BLAIR & COMPANY L.L.C.**, as of **12-31-2025**, are true and correct.

**Signature:** Michael Trimberger

**Title:** CFO