etf overlap · light overlap
IWM vs VB overlap
25% of IWM and VB is the same money, spread over 677 companies both funds hold.
Holdings as of September 24, 2026 · source: iShares (IWM), Vanguard (VB) · How we measured all 1,035 pairs
- same money
- same companies, extra weight
- only in this fund
What only one of them gives you
Where each fund puts its money
IWM and VB: what people ask
How much do IWM and VB overlap?
25% by weight, as of September 24, 2026: light overlap. 677 companies appear in both funds; they make up 69% of IWM and 25% of VB.
Which stocks do IWM and VB both hold?
The largest shared positions are TWST, TXG, MOG-A, FROG and HUT. Ranked by the smaller of the two weights, which is the part you would own twice.
Is it redundant to hold both IWM and VB?
Out of every $100 split evenly between them, about $25 (half in each fund) buys identical positions. The rest is exposure only one of the two funds gives you: 1,298 names only in IWM, 624 only in VB. Half in each behaves like 1,168 equally weighted stocks, against 842 for IWM alone and 674 for VB alone. Whether that duplication is a problem depends on the mix you want; this is a description, not advice.
How is ETF overlap calculated here?
For every company held by both funds we take the smaller of its two weights and add them up. The weights come from the full holdings files iShares and Vanguard publish, not a top-10 sample, and companies are matched by their ISIN so share classes stay apart. Sector overlap applies the same rule to the issuers' sector labels; "behaves like N equally weighted stocks" is one over the sum of the squared weights.
Weights come from each issuer's published holdings file and are matched company by company on their ISIN. Cash, futures and currency positions are left out. This page describes what the funds hold; it is not investment advice.