IJH vs IWM: how much do they really overlap?
IJH (iShares Core S&P Mid-Cap ETF, tracking the S&P MidCap 400) and IWM (iShares Russell 2000 ETF, tracking the Russell 2000) overlap by roughly 0% by weight. 0 of IJH's top 10 holdings also appear in IWM. A 50/50 blend of the two behaves like about 1945 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 IJH and IWM. The weight columns show how much of each fund each name represents.
| Holding | in IJH | in IWM |
|---|
Only in IJH
iShares Core S&P Mid-Cap ETF — US mid-cap. Its biggest holdings that IWM doesn’t have:
| TWLO TWILIO INC CLASS A | 0.86% |
| CRS CARPENTER TECHNOLOGY CORP | 0.84% |
| MKSI MKS | 0.82% |
| CW CURTISS WRIGHT CORP | 0.77% |
| NVT NVENT ELECTRIC PLC | 0.75% |
| ENTG ENTEGRIS INC | 0.75% |
| ATI ATI INC | 0.74% |
| ILMN ILLUMINA INC | 0.73% |
Only in IWM
iShares Russell 2000 ETF — US small-cap. Its biggest holdings that IJH doesn’t have:
| MOGA MOOG INC CLASS A | 0.38% |
| HUT HUT CORP | 0.37% |
| VSAT VIASAT INC | 0.35% |
| BTSG BRIGHTSPRING HEALTH SERVICES INC | 0.35% |
| CYTK CYTOKINETICS INC | 0.35% |
| MXL MAXLINEAR INC | 0.34% |
| AGX ARGAN INC | 0.34% |
| UMBF UMB FINANCIAL CORP | 0.33% |
So — essentially different. Should you hold both?
IJH and IWM hold almost none of the same securities — they are complementary, not redundant. Held together they genuinely broaden your exposure — a 50/50 blend reaches ~1945 effective positions (grade A), because they hold largely different securities.
Holdings as of — IJH: Jun 30, 2026 (iShares (BlackRock)); IWM: Jun 30, 2026 (iShares (BlackRock)). 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 →IJH vs IWM — FAQ
- How much do IJH and IWM overlap?
- IJH and IWM 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 IJH's 10 largest holdings are also held by IWM. They share 0 of their listed top holdings in total.
- Is it redundant to hold both IJH and IWM?
- 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 1945 positions and a A diversification grade.
- What does IWM hold that IJH doesn't?
- IWM's largest holdings that IJH doesn't hold include MOGA, HUT, VSAT, BTSG, CYTK. Its category is US small-cap, versus IJH's US mid-cap.
- Which is more concentrated, IJH or IWM?
- IJH's top 10 holdings are 27% of its listed weight; IWM's are 26%. The more concentrated fund leans harder on its largest names.