IWM vs VB: how much do they really overlap?
IWM (iShares Russell 2000 ETF, tracking the Russell 2000) and VB (Vanguard Small-Cap ETF, tracking the CRSP US Small Cap) overlap by roughly 0% by weight. 0 of IWM's top 10 holdings also appear in VB. A 50/50 blend of the two behaves like about 4501 equally-weighted bets (diversification grade A). In short, the two funds hold almost none of the same securities — they are complementary, not redundant.
The same companies, in both funds
These 0 holdings appear in both IWM and VB. The weight columns show how much of each fund each name represents.
| Holding | in IWM | in VB |
|---|
Only in IWM
iShares Russell 2000 ETF — US small-cap. Its biggest holdings that VB doesn’t have:
| XTSLA BLK CSH FND TREASURY SL AGENCY | 0.46% |
| MOGA MOOG INC CLASS A | 0.39% |
| BTSG BRIGHTSPRING HEALTH SERVICES INC | 0.38% |
| HUT HUT CORP | 0.36% |
| UMBF UMB FINANCIAL CORP | 0.35% |
| CYTK CYTOKINETICS INC | 0.34% |
| VSAT VIASAT INC | 0.32% |
| GKOS GLAUKOS CORP | 0.31% |
Only in VB
Vanguard Small-Cap ETF — US small-cap. Its biggest holdings that IWM doesn’t have:
| CRDO Credo Technology Group Holding Ltd. | 0.54% |
| JBL Jabil Inc. | 0.49% |
| RVMD Revolution Medicines Inc. | 0.45% |
| ALAB Astera Labs Inc. | 0.45% |
| NTRA Natera Inc. | 0.44% |
| EME EMCOR Group Inc. | 0.44% |
| TWLO Twilio Inc. Class A | 0.37% |
| NRG NRG Energy Inc. | 0.37% |
So — essentially different. Should you hold both?
IWM and VB hold almost none of the same securities — they are complementary, not redundant. Held together they genuinely broaden your exposure — a 50/50 blend reaches ~4501 effective positions (grade A), because they hold largely different securities.
Holdings as of — IWM: Jul 30, 2026 (iShares (BlackRock)); VB: Jun 30, 2026 (Vanguard). Refreshed monthly. Overlap is measured across each fund’s largest holdings (top 50); the diffuse long tail barely moves the math.
See this for YOUR whole portfolio, free →IWM vs VB — FAQ
- How much do IWM and VB overlap?
- IWM and VB overlap by approximately 0% measured by portfolio weight — that is the share of the smaller fund's holdings (by weight) that also sit inside the other. 0 of IWM's 10 largest holdings are also held by VB. They share 0 of their listed top holdings in total.
- Is it redundant to hold both IWM and VB?
- Because they hold almost none of the same securities — they are complementary, not redundant, holding both is not redundant — each fund covers largely different holdings, so together they broaden your exposure. A 50/50 blend has an effective 4501 positions and a A diversification grade.
- What does VB hold that IWM doesn't?
- VB's largest holdings that IWM doesn't hold include CRDO, JBL, RVMD, ALAB, NTRA. Its category is US small-cap, versus IWM's US small-cap.
- Which is more concentrated, IWM or VB?
- IWM's top 10 holdings are 26% of its listed weight; VB's are 27%. The more concentrated fund leans harder on its largest names.