FUBFX — Fidelity U.S. Bond Index Fund
Data updated: 2026-07-24
FUBFX — Fidelity U.S. Bond Index Fund data: holdings, portfolio allocation, expenses, performance, cashflows, risk and SEC filings. Long Total / Aggregate Bond · $69.05B AUM · 0.03% expense ratio. From SEC regulatory filings.
FUBFX Fund Overview
FUBFX — Fidelity U.S. Bond Index Fund is a US mutual fund managed by Fidelity Salem Street Trust, categorised as Long Total / Aggregate Bond. ABC INVEST provides holdings, performance, costs, cashflows, risk data, prospectus documents and SEC filings, sourced from SEC filings.
- Type: US mutual fund
- Manager: Fidelity Salem Street Trust
- Category: Long Total / Aggregate Bond
- Assets under management: $69.05B
- Ticker: FUBFX
- SEC CIK: 0000035315
- SEC series ID: S000017676
- Share class ID: C000079295
FUBFX Holdings
Top 10 holdings of Fidelity U.S. Bond Index Fund by percentage of net assets, from the fund's latest SEC N-PORT filing.
| Holding | % of net assets |
|---|---|
| Ust Notes | 0.93% |
| Ust Notes | 0.86% |
| Ust Notes | 0.84% |
| Ust Notes | 0.78% |
| Ust Notes | 0.73% |
| Ust Notes | 0.73% |
| Fed Home Loan Mtg Corp. - Gold | 0.63% |
| Ust Notes | 0.63% |
| Ust Notes | 0.59% |
| Ust Notes | 0.58% |
FUBFX Portfolio Allocation
Asset-class allocation of Fidelity U.S. Bond Index Fund by percentage of net assets, from the latest SEC N-PORT filing.
| Asset class | Allocation |
|---|---|
| Fixed Income | 74.6% |
| Securitized | 25.5% |
| Cash & Equivalents | 0.7% |
FUBFX Performance
Total returns for FUBFX (as of 2026-08-01), from SEC filings.
| Period | Total return |
|---|---|
| YTD | -1.3% |
FUBFX Costs and Fees
FUBFX costs about $3 per $10,000 invested per year in fund expenses.
- Net expense ratio: 0.03%
- Gross expense ratio: 0.03%
- Portfolio turnover: 45%
- Brokerage commissions: 0.00 bps of average net assets (SEC N-CEN)
FUBFX Cashflows
Over the 12 months to 2026-02, Fidelity U.S. Bond Index Fund had net inflows of $6.55B, from monthly SEC N-PORT filings.
| Month | Net flow |
|---|---|
| 2026-02 | $650.55M |
| 2026-01 | $649.85M |
| 2025-12 | $582.94M |
| 2025-11 | $289.99M |
| 2025-10 | $260.43M |
| 2025-09 | $615.52M |
FUBFX Debt Constituents
Largest debt holdings of Fidelity U.S. Bond Index Fund by percentage of net assets, from the latest SEC N-PORT filing.
| Debt holding | % of net assets |
|---|---|
| Ust Notes | 0.93% |
| Ust Notes | 0.86% |
| Ust Notes | 0.84% |
| Ust Notes | 0.78% |
| Ust Notes | 0.73% |
| Ust Notes | 0.73% |
| Ust Notes | 0.63% |
| Ust Notes | 0.59% |
| Ust Notes | 0.58% |
| Ust Notes | 0.58% |
FUBFX Prospectus and SEC Filings
Official Fidelity U.S. Bond Index Fund filings on SEC EDGAR — prospectus, portfolio holdings and annual reports.
Related Funds
Other Long Total / Aggregate Bond funds tracked on ABC INVEST:
Data Sources
ABC INVEST compiles this page from public filings made to the U.S. Securities and Exchange Commission (SEC) through EDGAR: portfolio holdings and monthly cashflows from Form N-PORT, expenses and returns from fund prospectuses (Form 485BPOS) and the SEC DERA Risk/Return Summary data sets, annual data from Form N-CEN, and shareholder reports from Form N-CSR.