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The most duplicated US ETF pairs

Edited by VoidLab· Data through 2026-09-04· Page updated 2026-09-04

Of the 117,855 pairs that the 486 US ETFs with a page here can form, the two funds that duplicate each other most are EZU and HEZU: 99.9% of their weight sits in the same 215 companies, on issuer files dated 2026-09-03. The median pair overlaps by 0.4%, 1.1% of pairs sit above 60% and 0.1% above 90%. Hold both funds of a pair near the top of this page and you add weight to the same companies rather than to new ones.

Which US ETF pairs are the most duplicated?

EZU and HEZU lead at 99.9%, followed by SPY and SPYM at 99.8% and EWJ and HEWJ at 99.8%. The 25 pairs below involve 35 funds; 12 of the pairs overlap by 98% or more inside one category, which is the rule this page uses for two funds tracking the same index, and 10 of the 25 pair funds from two different issuers. The lowest figure in the table is 96.3%, for PBUS and SPYM.

Columns, in both tables: Overlap is the overlap by weight; First in second is the share of the first fund's weight held in companies the second also holds, and Second in first reads the other way; In both is the number of companies held by both funds; Files gives the dates of the two issuer files, one date when they match.

Rows at 98% or more are marked. Compare opens the written comparison where one exists, and the ETF overlap calculator with both tickers filled in for every other pair.

Which pairs duplicate each other without tracking the same index?

Among funds that do not track the same index by the rule below, the most duplicated pair is IVV and SPY at 97.8%, both in Large Blend, with 501 companies in both and 98.6% of IVV also held in SPY. 12 pairs meet the same-index rule and are left out of this table. A pair on one index whose two files are dated weeks apart, or whose issuers spell a share class differently, can fall under the rule's line and land here, which is why both file dates are printed on every row.

Same index, as this page counts it: overlap by weight of 98% or more between two funds in the same Morningstar category. It is a rule applied to the figures, not a registry of which index each fund follows.

How is duplication measured here?

Overlap by weight is the sum, company by company, of the smaller weight each shared company has in the two funds, computed from the issuers' own holdings files with no estimate in between; a company at 6% of one fund and 4% of the other contributes 4 points. The share of one fund held in the other is the part of that fund's own weight sitting in companies the other also holds, so it reads differently from each side, and a small fund can be almost entirely inside a large one while making up a fraction of it. Companies in both is a plain count. A currency-hedged fund's file lists its underlying fund beside the forwards that hedge it, so its weights can sum to about 200% and its share held in common reads near 50% while the overlap by weight reads near 100%. Each fund's file is dated on its issuer's own schedule, so the two dates in a row are usually different, and a figure is only as current as the older of the two. The full definitions, with the return and correlation measures used elsewhere on the site, are on how the numbers are produced.

This page is rebuilt from the current files every trading day, so a row moves when an issuer publishes a new file. Any pair not shown here answers in the overlap calculator, in the portfolio x-ray for a whole basket, through the JSON API, or from an assistant through the MCP server. The 486 funds in the census are the ones with a page on the fund index.

Holdings from the issuer files behind the pairs listed, dated 2026-07-31 to 2026-09-05. Prices through 2026-09-04. Measurements of what funds hold, not investment advice.