Fidelity U.S. Bond Index Fund

Fidelity Salem Street Trust · Series S000017676 · 2 share classes

Bond fund · 100% debt· rate + credit risk filed
One fund, 2 share classes:FUBFXFXNAX
$69.05B NAV
10,442 positions · as of 2026-05-31 · filed 2026-07-24
data updated 2026-09-08

Fund profile

As filed in the prospectus · 2025 Q4

Fidelity U.S. Bond Index Fund seeks to provide investment results that correspond to the aggregate price and interest performance of the debt securities in the Bloomberg U.S. Aggregate Bond Index.

Strategy · summarised

The fund tracks the Bloomberg U.S. Aggregate Bond Index using statistical sampling techniques, holding a smaller number of securities selected by duration, maturity, interest rate sensitivity, structure, and credit quality to replicate index returns. Because the fund samples rather than holds all index constituents, its returns may diverge from the index. The fund may use derivatives including swaps, options, and futures to adjust risk exposure.

Expenses
0.03%one share class
Share classExpense ratio
FXNAX0.03%

Portfolio turnover 45.00% · as of 2025 Q4

Allocation

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

100.84%
of net assets
Bonds74.58%
Securitized25.59%
Cash & short-term0.68%

Latest quarter

What changed since the fund's previous filing

2026Q2 vs 2026Q1: 231 new226 exited

Largest new: UST NOTES ×7, GNMA II GTD PASS THRU CTF MULTIPLE ISSUER

Largest exited: UST NOTES ×6, GNMA II GTD PASS THRU CTF MULTIPLE ISSUER, FNMA/FHLG TBA ISSUER

Return profile

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

1-year
+4.04%
3-year
+10.68%
5-year
+0.76%
Volatility
3.45%
Worst 3-yr fall
-6.14%
Cumulative return· Jun 2023 – Apr 2026

May 2026 has been filed since the trailing figures were struck, so it is 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 2026-05-31

Avg coupon
3.07%
Avg maturity
12.32 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.

5%
floating
Fixed rate95.2%
Floating rate4.8%
Maturity ladder

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

<1y10y+
<1y2.6%
1-3y20.5%
3-5y16.6%
5-10y18.4%
10y+41.9%
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

More of this fund’s sensitivity sits in credit spreads than in interest rates — a rate rally that comes with a credit selloff works against it.

Interest-rate duration
5.80 yr
approx. move per 100bp
Credit-spread duration
5.90 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.

≈ -11.5%
of value
Credit spreads50%
Interest rates50%

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.

Credit risk by quality

Share of the fund's spread duration carried by each credit tier.

+5.90
yrs total
Investment grade+5.90 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 rate5.80 yr total
3 mo30 yr
3 mo0.01 yr0%
1 yr0.54 yr9%
5 yr1.44 yr25%
10 yr2.05 yr35%
30 yr1.76 yr30%
Credit spread5.90 yr total
3 mo30 yr
3 mo0.14 yr2%
1 yr0.93 yr16%
5 yr1.88 yr32%
10 yr2.05 yr35%
30 yr0.91 yr15%

The two bands measure the same positions against different shocks and do not add — a Treasury carries rate duration and no spread duration, a floating-rate credit the reverse. Rate tenors are also summed across every currency the fund discloses.

Show the numbers
TenorRate yrsIG yrsHY yrsIG $/bpHY $/bp
3 mo+0.01+0.14+0.00$962.0k$0
1 yr+0.54+0.93+0.00$6.43m$0
5 yr+1.44+1.88+0.00$12.96m$0
10 yr+2.05+2.05+0.00$14.13m$0
30 yr+1.76+0.91+0.00$6.28m$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
UST NOTES1.50% · due 2030-02-150.94%$645.27M
UST NOTES2.75% · due 2032-08-150.86%$595.71M
UST NOTES2.63% · due 2029-07-310.84%$577.54M
UST NOTES4.13% · due 2036-02-150.78%$536.45M
UST NOTES3.50% · due 2028-10-150.73%$506.51M
UST NOTES3.50% · due 2029-01-150.73%$501.35M
FED HOME LOAN MTG CORP - GOLD2.00% · due 2051-01-010.63%$435.08M
UST NOTES3.88% · due 2033-08-150.63%$432.79M
UST NOTES3.88% · due 2028-07-150.59%$410.21M
UST NOTES3.25% · due 2027-06-300.58%$403.72M
Showing 10 of 10,442Sign in to see more

Top 10 positions are 7.31% of net assets, top 25 14.52%, across 803 issuers.

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