etf overlap tool · little overlap
IWM vs CSPX overlap
IWM and CSPX hold no company in common. Still, 65% of their money sits in the same sectors, led by Information Technology, which is 38% of CSPX against 13% of IWM.
Holdings as of October 16, 2026 · source: iShares (IWM), iShares (CSPX) · How we measured all 1,431 pairs
- same money
- same companies, extra weight
- only in this fund
Hold IWM and CSPX with other funds or stocks? The free portfolio optimizer opens IWM and CSPX 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.
What only one of them gives you
AMZNAMAZON.COM INC3.72%No stock in common, 65% in the same sectors
IWM and CSPX: what people ask
How much do IWM and CSPX overlap?
None by holdings, as of October 16, 2026: no company appears in both funds. By sector, 65% of their money sits in the same sectors, led by Information Technology.
Which stocks do IWM and CSPX both hold?
None. IWM and CSPX have no holding in common.
Is it redundant to hold both IWM and CSPX?
No. Out of every $100 split evenly between them, none buys the same company. Half in each gives you 2,474 different holdings that behave like 169 equally weighted stocks, against 834 for IWM alone and 44 for CSPX alone. Whether that mix suits you depends on what you want to own; this is a description, not advice.
What is CSPX, next to IWM?
CSPX is iShares Core S&P 500 UCITS ETF (ISIN IE00B5BMR087), an Irish-domiciled UCITS fund on the S&P 500 index. Next to IWM, it holds no company in common, as of October 16, 2026.
Does the IWM vs CSPX overlap apply to other tickers?
Yes. CSPX also trades as CSP1 (London, GBP), SXR8 (Xetra, EUR) and CSSPX (Borsa Italiana, EUR). Each is the same portfolio in another currency, on another exchange or paying its dividends out, so IWM and SXR8 share no company either.
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 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.