State Street(R) SPDR(R) Portfolio Mortgage Backed Bond ETF

SPDR SERIES TRUST · 1 share class

U.S. bond index ETF
One fund, 1 share class:SPMB
$7.07B NAV
2,700 positions · as of 2026-06-30 · filed 2026-08-28

Fund classification

Classified from what the fund holds · as of 2026 Q2

State Street(R) SPDR(R) Portfolio Mortgage Backed Bond ETF is a U.S. bond index ETF that tracks the Bloomberg U.S. MBS Index.

Asset class
Bonds
Region
United States
Management
Index (passive)
Fund type
ETF
Rate sensitivity
Intermediate duration

Fund profile

As filed in the prospectus · 2025 Q4

The State Street SPDR Portfolio Mortgage Backed Bond ETF (the Fund) seeks to provide investment results that, before fees and expenses, correspond generally to the price and yield performance of an index that tracks the U.S. agency mortgage pass-through sector of the U.S. investment grade bond market.

Strategy · summarised

The fund tracks the Bloomberg U.S. MBS Index using a sampling strategy, holding a subset of agency mortgage pass-through securities grouped by issuer, coupon, and origination year and selected to replicate the index's risk and return characteristics. Because the fund samples rather than holds all index constituents, its performance may diverge from the index. The fund regularly enters into to-be-announced transactions, parking assets in money market instruments pending settlement.

Expenses
0.04%one share class
Share classExpense ratio
SPMB0.04%

Portfolio turnover 12.00% · as of 2025 Q4

Allocation

Asset groups · long / short shown separately, never netted · 2026 Q2

106.30%
of net assets
Securitized98.11%
Cash & short-term8.19%

These positions come to 106.30% of the fund's net assets. This counts only what the fund reported holding — the holdings disclosure covers assets, not liabilities such as borrowings — so it is not expected to reconcile to 100%.

Latest quarter

What changed since the fund's previous filing

2026Q2 vs 2026Q1: 76 new29 exited

Largest new: UMBS, TBA ×4, Government National Mortgage Association ×3, Freddie Mac

Largest exited: UMBS, TBA ×5, Government National Mortgage Association ×3

Return profile

Total return as filed — price change plus distributions reinvested · trailing figures to Apr 2026

1-year
+5.50%
3-year
+12.35%
5-year
+1.38%
Volatility
3.71%
Worst 3-yr fall
-7.20%
Cumulative return· Jul 2023 – Apr 2026

May 2026 and Jun 2026 have been filed since the trailing figures were struck, so they are not in the table above or the curve — every figure here shares one cut-off, which is what makes them comparable with other funds.

Debt profile

What this fund holds — value-weighted across its bond and securitized long positions · as of 2026-06-30

Avg coupon
3.70%
Avg maturity
24.89 yr
Coupon type

Share of the fund's debt by how its coupon behaves — the fact that decides whether a rate move reaches this portfolio at all.

0%
floating
Fixed rate100.0%
Maturity ladder

Share of the fund's debt value in each maturity band, shortest first.

<1y10y+
<1y0.0%
1-3y0.0%
3-5y0.1%
5-10y2.3%
10y+97.6%
Flagged holdings
Defaulted: none reported
In arrears: none reported
Paid in kind: none reported

Based on what filers reported; a filer that never reported a flag also reads as none.

Risk profile

Interest-rate and credit-spread sensitivity, both in years · as of 2026Q2

This fund filed the credit-spread disclosure and reported no sensitivity — measured, and the answer is none.

Interest-rate duration
5.55 yr
approx. move per 100bp
Credit-spread duration
0.00 yr
approx. move per 100bp
If rates and spreads both rise 100bp

Where the loss would come from. The two shocks are the same size, so this is the balance of the fund's two sensitivities rather than a bet on one moving more.

≈ -5.5%
of value
Interest rates100%

Filers report the impact of a 0.01% move only, so the total is our own scaling of that one number and overstates the loss on most bonds — read it as approximate, never as precise. The two sensitivities overlap rather than add up: they measure the same positions against different shocks, which is why the durations above are shown side by side and never summed.

Investment grade: +0.00 yrHigh yield: +0.00 yr
Where the risk sits on the curve

Share of duration at each point, shortest first. A positive figure loses value when spreads widen; a negative one offsets — a credit hedge.

Interest rate5.55 yr total
3 mo30 yr
3 mo0.02 yr0%
1 yr0.52 yr9%
5 yr1.41 yr25%
10 yr2.80 yr50%
30 yr0.80 yr14%
Show the numbers
TenorRate yrsIG yrsHY yrsIG $/bpHY $/bp
3 mo+0.02+0.00+0.00$0$0
1 yr+0.52+0.00+0.00$0$0
5 yr+1.41+0.00+0.00$0$0
10 yr+2.80+0.00+0.00$0$0
30 yr+0.80+0.00+0.00$0$0

Dollar change per 1bp of spread movement, as filed and sign-anchored. A blank cell was not filed; a zero was.

Holdings

By % of NAV · equity positions carry filed share counts · every resolvable issuer links to its company page

Issuer%NAVValue
State Street Global AdvisorsGVMXX8.19%$579.12M
Freddie Mac5.00% · due 2056-02-011.17%$83.05M
Fannie Mae2.00% · due 2052-02-010.79%$56.07M
Freddie Mac6.00% · due 2055-08-010.77%$54.10M
UMBS, TBA5.50% · due 2056-07-010.63%$44.54M
Freddie Mac2.50% · due 2052-05-010.61%$43.39M
Freddie Mac5.50% · due 2054-11-010.55%$39.01M
Government National Mortgage Association5.50% · due 2055-06-200.55%$38.65M
Fannie Mae4.50% · due 2052-08-010.51%$36.39M
Fannie Mae5.50% · due 2055-02-010.49%$34.71M
Showing 10 of 2,700Sign in to see more

Top 10 positions are 14.27% of net assets, top 25 20.69%, across 5 issuers.

See more of this fund's book

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