etf overlap · nearly the same fund
SPY vs ITOT overlap
89% of SPY and ITOT is the same money, spread over 501 companies both funds hold.
Holdings as of September 24, 2026 · source: SPDR (SPY), iShares (ITOT) · How we measured all 1,035 pairs
- same money
- same companies, extra weight
- only in this fund
The companies you would own twice
What only one of them gives you
Where each fund puts its money
SPY and ITOT: what people ask
Is ITOT the same as SPY?
Nearly: 89% of the money in SPY and ITOT sits in the same companies at the same weights, as of September 24, 2026. The other 11% is weight differences, plus 3 names only in SPY and 1,924 only in ITOT.
How much do SPY and ITOT overlap?
89% by weight, as of September 24, 2026: nearly the same fund. 501 companies appear in both funds; they make up 100% of SPY and 89% of ITOT.
Which stocks do SPY and ITOT both hold?
The largest shared positions are NVDA, AAPL, MSFT, AMZN and GOOGL. Ranked by the smaller of the two weights, which is the part you would own twice.
Is it redundant to hold both SPY and ITOT?
Out of every $100 split evenly between them, about $89 (half in each fund) buys identical positions. The rest is exposure only one of the two funds gives you: 3 names only in SPY, 1,924 only in ITOT. Half in each behaves like 49 equally weighted stocks, against 44 for SPY alone and 55 for ITOT 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 SPDR and iShares 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.