etf overlap · 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 39% of CSPX against 14% of IWM.

Holdings as of September 24, 2026 · source: iShares (IWM), iShares (CSPX) · How we measured all 1,431 pairs

overlapfull holdings, by weight
0.0%of each fund is money the other holds at the same weight, across 0 shared companies.
IWM
100%
CSPX
100%
  • same money
  • same companies, extra weight
  • only in this fund
Overlap = the sum, over companies both funds hold, of the smaller of the two weights. Cash and derivatives excluded.
01Different

What only one of them gives you

only in IWM1,975 names
TWTWSTTWIST BIOSCIENCE0.40%
MOMOG-AMOOG INC CLASS A0.36%
HUHUTHUT CORP0.35%
FRFROGJFROG0.34%
UMUMBFUMB FINANCIAL0.33%
TXTXG10X GENOMICS CLASS A0.33%
VSVSATVIASAT INC0.31%
BTBTSGBRIGHTSPRING HEALTH SERVICES INC0.31%
only in CSPX504 names
NVIDIA logoNVDANVIDIA8.05%
APPLE logoAAPLAPPLE7.52%
MICROSOFT logoMSFTMICROSOFT5.95%
AMAZON.COM INC logoAMZNAMAZON.COM INC3.75%
ALPHABET CLASS A logoGOOGLALPHABET CLASS A3.07%
BROADCOM INC logoAVGOBROADCOM INC2.48%
ALPHABET CLASS C logoGOOGALPHABET CLASS C2.45%
META PLATFORMS CLASS A logoMETAMETA PLATFORMS CLASS A2.44%
02Sectors

No stock in common, 65% in the same sectors

sectorsIWM vs CSPX, share of each fund
Information Technology13.72%38.67%
Financials19.01%11.52%
Health Care20.35%9.46%
Industrials14.05%7.98%
Consumer Discretionary8.77%8.73%
Communication Services2.45%9.80%
Energy6.76%3.71%
Real Estate5.68%1.70%
Consumer Staples1.95%4.72%
Materials4.21%1.63%
Utilities2.68%1.97%
03Questions

IWM and CSPX: what people ask

questions6 answered

How much do IWM and CSPX overlap?

None by holdings, as of September 24, 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 2,479 different holdings that behave like 166 equally weighted stocks, against 842 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 September 24, 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.

Hold IWM and CSPX?Import your positions and see what your funds hold together, company by company, with the fees you pay on each.Import my portfolio

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.