MUB vs SPY: Holdings Overlap
MUBiShares National Muni Bond ETF
iShares · 6603 holdings · $45.3B · as of 2026-05-31
SPYState Street® SPDR® S&P 500® ETF Trust
State Street (SPDR) · 504 holdings · $812.0B · as of 2026-08-06
Holdings snapshots are 67 days apart (MUB: 2026-05-31, SPY: 2026-08-06). Weights and index membership change between snapshots, so the true current overlap is typically higher than shown. For funds tracking the same index, the gap can be 5–15 points.
How similar are MUB and SPY?
iShares National Muni Bond ETF (MUB, by iShares) holds 6603 positions; State Street® SPDR® S&P 500® ETF Trust (SPY, by State Street (SPDR)) holds 504. They have 0 holdings in common, and by portfolio weight the two funds are 0.0% identical. In practical terms the pair is essentially distinct, holding almost none of the same securities.
- Overlap by Weight
- 0.0%Sum of the smaller weight of each shared holding
- Shared Holdings
- 0MUB holds 6603 · SPY holds 504
- Weight in Shared Holdings
- MUB 0%·SPY 0%Share of each fund's weight in stocks both funds own
Based on each fund's latest official holdings. How is this calculated?
What makes each fund different
Only in MUB
6603 of 6603 positions (95.6% of the fund) are not held by SPY. Showing the top 30 by weight.
- Board of Regents of the University of Texas System, Series 2025B0.19%
- New York State Thruway Authority, Series 2022A0.15%
- New York State Dormitory Authority, Series 2019D0.13%
- Ohio State University (The), Series 2026A0.13%
- Houston Higher Education Finance Corp., Series 20240.13%
- Northwest Independent School District, Series 20250.13%
Performance
| Fund | 1M | YTD | 1Y | 3Y (ann.) | 5Y (ann.) | 10Y (ann.) | Yield |
|---|---|---|---|---|---|---|---|
| MUB | -0.9% | +0.8% | +5.1% | +3.3% | +0.7% | +1.9% | 3.22% |
| SPY | +3.4% | +14.0% | +23.7% | +21.2% | +13.3% | +15.3% | 0.97% |
Total returns including dividends, from adjusted daily closes as of 2026-08-07. 3Y/5Y/10Y are annualized. Yield is trailing-12-month distributions over the last close. Past performance does not predict future results.
Project the growth of $10,000 in MUB vs SPY →
Shared Holdings(0)
These two funds have no holdings in common.
Frequently Asked Questions
How much do MUB and SPY overlap?
MUB and SPY overlap by 0.0% of portfolio weight. They share 0 holdings (MUB holds 6603 positions and SPY holds 504), based on each fund's latest SEC-reported holdings.
Is it redundant to own both MUB and SPY?
The two portfolios are 0.0% identical by weight. Owning both is genuine diversification: the funds hold almost none of the same securities.
What does MUB own that SPY doesn't?
6603 positions (95.6% of MUB) are unique to MUB, led by Board of Regents of the University of Texas System, Series 2025B, New York State Thruway Authority, Series 2022A and New York State Dormitory Authority, Series 2019D. In the other direction, 504 positions (99.9% of SPY) are unique to SPY.