IEMG vs SPY: 0% overlap

iShares Core MSCI Emerging Markets ETF and SPDR S&P 500 ETF Trust share 0.1% of their portfolios by weight — computed as Σ min(wA, wB) over every holding both funds own.

Hold both, 50/50
2.0Effective Funds

You would hold two tickers and get the diversification of 2.0. Two funds that shared nothing would score 2.0; two identical funds score 1.0.

Overlap
0.1%
IEMG expense ratio
0.09%
SPY expense ratio
0.09%

Top shared holdings

IEMG and SPY hold 9 of the same securities. The ten contributing most to the overlap figure:

Holdingin IEMGin SPYΔ
HAL0.1%0.0%0.0%
BDX0.0%0.1%0.0%
TEL0.0%0.1%0.1%
CCL0.0%0.1%0.0%
ECL0.0%0.1%0.1%
LULU0.0%0.0%0.0%
SRE0.0%0.1%0.1%
IEX0.0%0.0%0.0%
PTC0.0%0.0%0.0%

Where IEMG and SPY differ

Sector weights as a share of each fund, ordered by the size of the gap rather than the size of the sector — two funds that overlap heavily still usually diverge somewhere.

SectorIEMGSPYΔ
Health Care3.1%9.1%6.0pp
Financials18.1%12.4%+5.7pp
Materials5.8%1.8%+4.0pp
Communication Services5.4%9.3%3.9pp
Information Technology39.8%37.5%+2.3pp
Consumer Staples3.0%4.6%1.6pp
Industrials7.7%8.9%1.1pp
Cash and/or Derivatives0.8%0.0%+0.8pp

Δ is IEMG minus SPY, in percentage points. Sector data is not published by every issuer, so “Unclassified” is a real category rather than a gap in the table.

What each fund holds alone

Only in IEMG
2,780 positions

99.1% of IEMG by weight, held in no part of SPY.

Only in SPY
495 positions

99.4% of SPY by weight, held in no part of IEMG.

A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.

Concentration and cost

IEMGSPY
Top 10 holdings33.6%36.9%
Positions held2,790505
Cost per $10,000 held, per year$9$9

Cost is the expense ratio applied to $10,000; it excludes any brokerage commission, bid-ask spread or tax consequence. Figures are facts about the funds, not a suggestion about which to hold.

Frequently asked

How much do IEMG and SPY overlap?

IEMG and SPY overlap 0.1% by portfolio weight — largely distinct portfolios. They share 9 holdings. The figure comes from current issuer holdings files (IEMG as of 2026-07-23, SPY as of 2026-07-23).

How is the overlap between IEMG and SPY calculated?

As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If IEMG holds a stock at 6% and SPY holds the same stock at 4%, 4% counts as shared. The result is bounded between 0% and 100%, and it is computed after looking through any fund-of-funds to the underlying holdings.

Is it redundant to hold both IEMG and SPY?

That depends on your goals — we state facts, not advice. At 0.1% overlap, each fund still contributes meaningfully distinct exposure.

What does IEMG own that SPY doesn't?

IEMG holds 2,790 positions and SPY holds 505; 2,780 of IEMG's positions don't appear in SPY at all, and they are 99.1% of IEMG by weight.

You probably hold more than two funds

This page compares IEMG and SPY. Paste your whole portfolio — brokerage, 401(k), IRA — and see the overlap across every fund at once, plus what you actually own underneath them and your own Effective Funds number. Free, no account, nothing stored.

X-ray my portfolio — free →

Watch IEMG vs SPY

We re-read both funds’ published holdings every weeknight. Leave an address and we'll tell you when what's inside actually changes.

Not sending yet — email alerts are built but switched off, and you'll be among the first when they turn on. No spam, one-click unsubscribe.

Related comparisons

Sources: issuer holdings files, IEMG as of 2026-07-23, SPY as of 2026-07-23. Weights are fractions of each fund. Diagnostics, not advice.