IWM vs VFIFX: 3% overlap
iShares Russell 2000 ETF and Vanguard Target Retirement 2050 share 3.1% of their portfolios by weight — computed as Σ min(wA, wB) over every holding both funds own.
Different holding dates. These holdings were published about 4 months apart — VFIFX as of 2026-03-31, the rest through 2026-07-23. Each fund is compared using its most recent file, so any trading in between shows up as a difference.
You would hold two tickers and get the diversification of 2.0. Two funds that shared nothing would score 2.0; two identical funds score 1.0.
Top shared holdings
IWM and VFIFX hold 1,839 of the same securities. The ten contributing most to the overlap figure:
| Holding | in IWM | in VFIFX | Δ |
|---|---|---|---|
| CASH | 0.2% | 1.9% | 1.7% |
| MC | 0.1% | 0.1% | 0.0% |
| AIR | 0.2% | 0.1% | 0.1% |
| CNR | 0.1% | 0.1% | 0.1% |
| ENR | 0.0% | 0.1% | 0.1% |
| ORA | 0.2% | 0.0% | 0.2% |
| UCB | 0.1% | 0.0% | 0.1% |
| AI | 0.0% | 0.0% | 0.0% |
| CCO | 0.0% | 0.0% | 0.0% |
| ACA | 0.2% | 0.0% | 0.2% |
Where IWM and VFIFX differ
Sector weights as a share of each fund, ordered by the size of the gap rather than the size of the sector — two funds that overlap heavily still usually diverge somewhere.
| Sector | IWM | VFIFX | Δ |
|---|---|---|---|
| Information Technology | 12.8% | 26.1% | −13.2pp |
| Health Care | 19.9% | 6.9% | +12.9pp |
| Unclassified | 0.0% | 6.3% | −6.3pp |
| Financials | 19.0% | 14.1% | +5.0pp |
| Industrials | 14.7% | 10.5% | +4.2pp |
| Real Estate | 5.9% | 1.9% | +4.1pp |
| Treasuries | 0.0% | 3.6% | −3.6pp |
| Communication Services | 2.5% | 5.9% | −3.4pp |
Δ is IWM minus VFIFX, in percentage points. Sector data is not published by every issuer, so “Unclassified” is a real category rather than a gap in the table.
What each fund holds alone
4.2% of IWM by weight, held in no part of VFIFX.
94.9% of VFIFX by weight, held in no part of IWM.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| IWM | VFIFX | |
|---|---|---|
| Top 10 holdings | 3.3% | 19.3% |
| Positions held | 1,967 | 6 |
| Cost per $10,000 held, per year | $19 | $8 |
Cost is the expense ratio applied to $10,000; it excludes any brokerage commission, bid-ask spread or tax consequence. Figures are facts about the funds, not a suggestion about which to hold.
Frequently asked
How much do IWM and VFIFX overlap?
IWM and VFIFX overlap 3.1% by portfolio weight — largely distinct portfolios. They share 1,839 holdings. The figure comes from current issuer holdings files (IWM as of 2026-07-23, VFIFX as of 2026-03-31).
How is the overlap between IWM and VFIFX calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If IWM holds a stock at 6% and VFIFX holds the same stock at 4%, 4% counts as shared. The result is bounded between 0% and 100%, and it is computed after looking through any fund-of-funds to the underlying holdings.
Is it redundant to hold both IWM and VFIFX?
That depends on your goals — we state facts, not advice. At 3.1% overlap, each fund still contributes meaningfully distinct exposure.
What does IWM own that VFIFX doesn't?
IWM holds 1,967 positions and VFIFX holds 6; 127 of IWM's positions don't appear in VFIFX at all, and they are 4.2% of IWM by weight.
You probably hold more than two funds
This page compares IWM and VFIFX. Paste your whole portfolio — brokerage, 401(k), IRA — and see the overlap across every fund at once, plus what you actually own underneath them and your own Effective Funds number. Free, no account, nothing stored.
X-ray my portfolio — free →Watch IWM vs VFIFX
We re-read both funds’ published holdings every weeknight. Leave an address and we'll tell you when what's inside actually changes.
Not sending yet — email alerts are built but switched off, and you'll be among the first when they turn on. No spam, one-click unsubscribe.
Related comparisons
Sources: issuer holdings files, IWM as of 2026-07-23, VFIFX as of 2026-03-31. Weights are fractions of each fund. Diagnostics, not advice.