Fidelity U.S. Bond Index Fund
Fidelity Salem Street Trust · Series S000017676 · 2 share classes
data updated 2026-08-10
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.
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.
| Share class | Expense ratio |
|---|---|
| FXNAX | 0.03% |
Portfolio turnover 45.00% · as of 2025 Q4
Allocation
Asset groups · long / short shown separately, never netted · 2026 Q1
| Bonds | 73.63% |
| Securitized | 26.30% |
| Cash & short-term | 1.33% |
Latest quarter
What changed since the fund's previous filing
Largest new: UST NOTES ×5, UNITED STATES TREASURY BOND ×2, GNMA II GTD PASS THRU CTF MULTIPLE ISSUER
Largest exited: UST NOTES, UNITED STATES TREASURY BOND ×2, GNMA II GTD PASS THRU CTF MULTIPLE ISSUER ×3, FED HOME LOAN MTG CORP - GOLD, FNMA GTD MTG PASS THRU CTF
Return profile
Total return as filed — price change plus distributions reinvested · trailing figures to Feb 2026
Debt profile
What this fund holds — value-weighted across its bond and securitized long positions · as of 2026-02-28
Share of the fund's debt by how its coupon behaves — the fact that decides whether a rate move reaches this portfolio at all.
| Fixed rate | 95.4% |
| Floating rate | 4.6% |
Share of the fund's debt value in each maturity band, shortest first.
| <1y | 3.7% |
| 1-3y | 19.4% |
| 3-5y | 15.7% |
| 5-10y | 18.0% |
| 10y+ | 43.2% |
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 2026Q1
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.
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.
| Credit spreads | 50% |
| Interest rates | 50% |
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.
Share of the fund's spread duration carried by each credit tier.
| Investment grade | +5.89 yr |
Share of duration at each point, shortest first. A positive figure loses value when spreads widen; a negative one offsets — a credit hedge.
| 3 mo | 0.02 yr | 0% |
| 1 yr | 0.55 yr | 9% |
| 5 yr | 1.44 yr | 25% |
| 10 yr | 2.03 yr | 35% |
| 30 yr | 1.78 yr | 31% |
| 3 mo | 0.14 yr | 2% |
| 1 yr | 0.92 yr | 16% |
| 5 yr | 1.86 yr | 32% |
| 10 yr | 2.03 yr | 35% |
| 30 yr | 0.94 yr | 16% |
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
| Tenor | Rate yrs | IG yrs | HY yrs | IG $/bp | HY $/bp |
|---|---|---|---|---|---|
| 3 mo | +0.02 | +0.14 | +0.00 | $985.4k | $0 |
| 1 yr | +0.55 | +0.92 | +0.00 | $6.46m | $0 |
| 5 yr | +1.44 | +1.86 | +0.00 | $13.08m | $0 |
| 10 yr | +2.03 | +2.03 | +0.00 | $14.31m | $0 |
| 30 yr | +1.78 | +0.94 | +0.00 | $6.59m | $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
| Ticker | Issuer | %NAV | Value | Shares |
|---|---|---|---|---|
| — | UST NOTES1.50% · due 2030-02-15 | 0.93% | $657.10M | — |
| — | UST NOTES2.75% · due 2032-08-15 | 0.87% | $613.48M | — |
| — | UST NOTES2.63% · due 2029-07-31 | 0.83% | $587.81M | — |
| — | Fidelity Revere Street Trust | 0.83% | $581.02M | — |
| — | UST NOTES3.75% · due 2028-05-15 | 0.82% | $577.15M | — |
| — | UST NOTES3.50% · due 2028-10-15 | 0.73% | $514.04M | — |
| — | UST NOTES3.50% · due 2029-01-15 | 0.72% | $509.75M | — |
| — | FED HOME LOAN MTG CORP - GOLD2.00% · due 2051-01-01 | 0.65% | $458.32M | — |
| — | UST NOTES3.88% · due 2033-08-15 | 0.64% | $447.63M | — |
| — | UST NOTES3.88% · due 2028-07-15 | 0.59% | $415.97M | — |
Top 10 positions are 7.62% of net assets, top 25 15.11%, across 800 issuers.
See more of this fund's book
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