Guide · US Small Cap
Best small-cap ETFs
VTI already holds small-caps at 6–8% of the fund. A dedicated small-cap ETF is an overweight, not a hole being filled. VB is 3 bps and market-cap weighted. IJR's S&P 600 adds a profitability screen. IWM is the Russell 2000 everyone quotes on TV, at 19 bps. AVUV is the small-cap-value tilt that shows up in Golden Butterfly and on the Bogleheads factor threads.
Published May 18, 2026 · Updated Sep 16, 2026 · Fund data as of Oct 24, 2026
Why the ranking looks like this
Cost separates the field cleanly. VB, VBR, and IJR run at 3-6 bps and dominate the top of the leaderboard; IWM (the Russell 2000 fund every news anchor quotes) costs 19 bps for similar exposure. AVUV is the small-cap-value fund Boglehead factor-tilt investors specifically reach for — it costs more (25 bps) but applies a quality + value screen on top of the size cut.
See the methodology for the full formula behind each sub-score.
The funds
This order is editorial. The composite on each card is live. The full score-ranked table is on the category page.
-
96
composite / 100
Vanguard's broad small-cap fund. 3 bps. Tracks the Morningstar US Small Cap Index (formerly the CRSP US Small Cap Index) — broad market-cap-weighted small-cap, no factor screening. SCHA and SPSM sit within a tenth of a point of it on the composite at the same fee.
- Expense
- 0.030%
- AUM
- $175.77B†
- Issuer
- Vanguard
- Detail
- VB page →
-
95
composite / 100
Vanguard's small-cap value fund. 5 bps; Morningstar (formerly CRSP) small-cap-value index. The middle ground for investors who want a value tilt on top of small-cap without paying the AVUV premium.
- Expense
- 0.050%
- AUM
- $64.12B†
- Issuer
- Vanguard
- Detail
- VBR page →
-
95
composite / 100
iShares' S&P SmallCap 600 fund. 6 bps; tracks the S&P 600, which screens for profitable small-cap names — modestly higher quality tilt than the Russell 2000. Works as a tax-loss-harvesting partner to VB.
- Expense
- 0.060%
- AUM
- $102.56B
- Issuer
- iShares
- Detail
- IJR page →
-
90
composite / 100
iShares' Russell 2000 fund. 19 bps — the most-traded small-cap ETF on the market but six times the cost of VB for similar exposure. The natural fund for short-term traders (deep options market) but not the preferred long-term holding.
- Expense
- 0.19%
- AUM
- $78.04B
- Issuer
- iShares
- Detail
- IWM page →
-
88
composite / 100
Avantis US Small Cap Value ETF. 25 bps; applies a value + profitability screen on top of a small-cap universe. The most-cited factor-tilt fund on Boglehead forums; meaningfully different exposure from the index-tracking small-cap options above.
- Expense
- 0.25%
- AUM
- $30.38B
- Issuer
- Avantis
- Detail
- AVUV page →
† Whole fund: this ETF is one share class of a fund that also sells mutual-fund shares, and the figure covers all of them. Our sources don't report the ETF class on its own.
Also in the category
Other funds in the same category, ranked by composite score.
Small-cap vs total market
A US total-market fund (VTI) holds small-caps at about 6-8% of the fund by market cap. Adding a small-cap sleeve overweights that — a common Boglehead-style tilt is to hold 80% total-market plus 20% small-cap value, which roughly doubles the small-cap exposure of the overall portfolio. The size premium is real but episodic, and multi-year stretches of underperformance against large-cap are the normal shape of the bet rather than a sign it has broken.
Russell 2000 vs S&P SmallCap 600
These are the two largest small-cap indexes, and they hold different stocks. The Russell 2000 includes any company in the smaller half of the Russell 3000 universe, with no profitability requirement. The S&P SmallCap 600 includes a profitability screen — companies must have positive trailing earnings to be added. The S&P 600 has historically delivered slightly higher returns at similar risk; the difference is small enough to be in the "interesting trivia" bucket for most investors.
Funds are pulled from the live composite for this category. Notes are editorial and refresh with the catalog.
PlainIndex publishes data and editorial commentary — nothing here is personalized investment advice. Read the methodology for how the scores referenced here are computed.