etf overlap tool · nearly the same fund
SPY vs VTI overlap
88% of SPY and VTI is the same money, spread over 501 companies both funds hold.
Holdings as of September 30, 2026 · source: SPDR (SPY), Vanguard (VTI) · How we measured all 1,431 pairs
- same money
- same companies, extra weight
- only in this fund
Swapping one for the other to harvest a loss? In our study of 32 tax-loss harvesting ETF pairs, SPY and VTI correlated 0.9963 over the 261 weeks to October 16, 2026 and were never more than 1 point apart in a week; over the year to that date, SPY returned 0.52 points more than VTI. IRS Publication 550 sets no test for when two ETFs are “substantially identical” under the wash-sale rule: it says to consider “all the facts and circumstances in your particular case,” so no correlation figure settles the question.
Hold SPY and VTI with other funds or stocks? The free portfolio optimizer opens SPY and VTI beside the rest of what you own: the companies you hold twice, what the funds cost a year, and where the next deposit should go. No account.
The companies you would own twice
GOOGALPHABET INC CL C2.43%2.18%
What only one of them gives you
Where each fund puts its money
SPY and VTI: what people ask
Is VTI the same as SPY?
Nearly: 88% of the money in SPY and VTI sits in the same companies at the same weights, as of September 30, 2026. The other 12% is weight differences, plus 3 names only in SPY and 3,015 only in VTI.
How much do SPY and VTI overlap?
88% by weight, as of September 30, 2026: nearly the same fund. 501 companies appear in both funds; they make up 99.7% of SPY and 89% of VTI.
Which stocks do SPY and VTI 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 VTI?
Out of every $100 split evenly between them, about $88 (half in each fund) buys identical positions. The rest is exposure only one of the two funds gives you: 3 names only in SPY, 3,015 only in VTI. Half in each behaves like 49 equally weighted stocks, against 44 for SPY alone and 55 for VTI 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 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.