WBSIX — William Blair Small Cap Growth Fund
Data updated: 2026-05-28
WBSIX — William Blair Small Cap Growth Fund data: holdings, portfolio allocation, expenses, performance, cashflows, risk and SEC filings. United States Small Cap Growth Equity · $992.29M AUM · 1.25% expense ratio · 13.8% 1-yr return. From SEC regulatory filings.
WBSIX Fund Overview
WBSIX — William Blair Small Cap Growth Fund is a US mutual fund managed by William Blair Funds, categorised as United States Small Cap Growth Equity. ABC INVEST provides holdings, performance, costs, cashflows, risk data, prospectus documents and SEC filings, sourced from SEC filings.
- Type: US mutual fund
- Manager: William Blair Funds
- Category: United States Small Cap Growth Equity
- Assets under management: $992.29M
- 1-year return: 13.8%
- Ticker: WBSIX
- SEC CIK: 0000822632
- SEC series ID: S000008602
- Share class ID: C000023541
WBSIX Holdings
Top 10 holdings of William Blair Small Cap Growth Fund by percentage of net assets, from the fund's latest SEC N-PORT filing.
| Holding | % of net assets |
|---|---|
| Fixed Income Clearing Corp. | 3.73% |
| Diebold Nixdorf Inc | 2.46% |
| Twist Bioscience Corp | 2.15% |
| Balchem Corp | 1.86% |
| Cognex Corp | 1.73% |
| Marex Group PLC | 1.73% |
| Rush Street Interactive Inc | 1.61% |
| Garrett Motion Inc | 1.61% |
| Regal Rexnord Corp | 1.59% |
| Globus Medical Inc | 1.57% |
WBSIX Portfolio Allocation
Asset-class allocation of William Blair Small Cap Growth Fund by percentage of net assets, from the latest SEC N-PORT filing.
| Asset class | Allocation |
|---|---|
| Equity | 96.3% |
| Cash & Equivalents | 3.7% |
WBSIX Performance
Total returns for WBSIX (as of 2026-08-01), from SEC filings.
| Period | Total return |
|---|---|
| YTD | -1.7% |
| 1 year | 13.8% |
| 3 years (annualised) | 9.7% |
| 5 years (annualised) | 3.0% |
WBSIX Risk Information
Risk metrics for WBSIX, derived from monthly returns in SEC filings.
- 1-year volatility (annualised): 13.1%
WBSIX Costs and Fees
WBSIX costs about $125 per $10,000 invested per year in fund expenses.
- Net expense ratio: 1.25%
- Gross expense ratio: 1.12%
- Portfolio turnover: 94%
- Brokerage commissions: 7.26 bps of average net assets (SEC N-CEN)
WBSIX Cashflows
Over the 12 months to 2026-03, William Blair Small Cap Growth Fund had net inflows of $94.73M, from monthly SEC N-PORT filings.
| Month | Net flow |
|---|---|
| 2026-03 | $10.95M |
| 2026-02 | −$3.30M |
| 2026-01 | $14.94M |
| 2025-12 | $40.24M |
| 2025-11 | −$25.05M |
| 2025-10 | $47.05M |
WBSIX Debt Constituents
No individual debt constituents are reported in William Blair Small Cap Growth Fund's latest SEC N-PORT filing.
WBSIX Prospectus and SEC Filings
Official William Blair Small Cap Growth Fund filings on SEC EDGAR — prospectus, portfolio holdings and annual reports.
Related Funds
Other United States Small Cap Growth Equity funds tracked on ABC INVEST:
Data Sources
ABC INVEST compiles this page from public filings made to the U.S. Securities and Exchange Commission (SEC) through EDGAR: portfolio holdings and monthly cashflows from Form N-PORT, expenses and returns from fund prospectuses (Form 485BPOS) and the SEC DERA Risk/Return Summary data sets, annual data from Form N-CEN, and shareholder reports from Form N-CSR.