SPMB
US Aggregate BondState Street SPDR Portfolio Mortgage Backed Bond ETF
State Street · Tracks Bloomberg US MBS Index · Inception Jan 15, 2009
Trailing returns
through Oct 23, 2026- 1 year
- -0.4%
- 3 year
- +6.0%
- annualized
- 5 year
- +0.1%
- annualized
Price return from month-end closes, distributions reinvested at month end. Excludes trading costs, bid-ask spreads and taxes. Past performance says nothing about future returns and is not part of the composite score — see the methodology for what the score does measure.
Composite score
Based on a 0.040% expense ratio.
Based on $6.82B in net assets.
Top-10 holdings represent 6.6% of net assets.
US Aggregate Bond base · ETF wrapper · 4.27% TTM yield.
The composite is a weighted average of the four core sub-scores above (cost, tax efficiency, liquidity, concentration). Missing sub-scores fall back to the per-category median when the category has at least 50% data coverage, so funds without (e.g.) parsed N-PORT holdings aren't accidentally boosted by renormalization. Tracking quality is shown where computable but isn't currently part of the composite weighting. See methodology for formulas, the tracking-quality partial-coverage rationale, and the dimensions we deliberately don't score (methodology v0.5.2).
Look through SPMB, or compare the fee
Tool · Look-through
Underlying holdings, with other funds added
Add tickers and weights; N-PORT positions are summed across the basket.
Tool · Cost
Compare SPMB's fee against another fund
Compounds the 0.040% expense ratio against a peer over decades.
Tool · Overlap
Compare SPMB's holdings with peers
Pairwise holdings heatmap, pre-loaded with similar US Aggregate Bond funds.
Tool · TLH
Find a tax-loss harvesting partner for SPMB
Ranks every catalog fund by holdings overlap, flags wash-sale risk.
Tool · Placement
Asset location for SPMB across account types
Asset-location optimizer — places each fund in taxable / tax-deferred / Roth.
Top holdings
| # | Holding | Weight |
|---|---|---|
| 1 | Freddie Mac | 1.17% |
| 2 | Fannie Mae | 0.79% |
| 3 | Freddie Mac | 0.76% |
| 4 | UMBS, TBA | 0.63% |
| 5 | Freddie Mac | 0.61% |
| 6 | Freddie Mac | 0.55% |
| 7 | Government National Mortgage Association | 0.55% |
| 8 | Fannie Mae | 0.51% |
| 9 | Fannie Mae | 0.49% |
| 10 | Fannie Mae | 0.47% |
Compare SPMB with another fund
Or skim the closest-overlap funds below.
Similar ETFs by holdings overlap
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