# Portfolio overlap — FUBFX vs FIFZX

Comparing **Fidelity U.S. Bond Index Fund** (2026-02-28) and **Fidelity Series Bond Index Fund** (2026-02-28).

- Shared positions: 7387
- Fidelity U.S. Bond Index Fund covered by Fidelity Series Bond Index Fund: 0.5927618344384474079658221586
- Fidelity Series Bond Index Fund covered by Fidelity U.S. Bond Index Fund: 0.5927618344384474079658221586

## Fidelity U.S. Bond Index Fund — top positions

| Security | Weight | Shared |
|----------|--------|--------|
| US TREASURY N/B | 0.009120 | ✓ |
| US TREASURY N/B | 0.008514 | ✓ |
| US TREASURY N/B | 0.008158 | ✓ |
| Fidelity Cash Central Fund | 0.008064 | ✓ |
| US TREASURY N/B | 0.008010 | ✓ |
| US TREASURY N/B | 0.007134 | ✓ |
| US TREASURY N/B | 0.007075 | ✓ |
| FR SD8121 | 0.006361 | ✓ |
| US TREASURY N/B | 0.006213 | ✓ |
| US TREASURY N/B | 0.005773 | ✓ |
| US TREASURY N/B | 0.005758 | ✓ |
| US TREASURY N/B | 0.005756 | ✓ |
| US TREASURY N/B | 0.005560 | ✓ |
| US TREASURY N/B | 0.005290 | ✓ |
| US TREASURY N/B | 0.005183 | ✓ |
| Fidelity Securities Lending Cash Central Fund | 0.004969 | ✓ |
| US TREASURY N/B | 0.004808 | ✓ |
| US TREASURY N/B | 0.004701 | ✓ |
| US TREASURY N/B | 0.004599 | ✓ |
| US TREASURY N/B | 0.004561 | ✓ |
| US TREASURY N/B | 0.004423 | ✓ |
| US TREASURY N/B | 0.004406 | ✓ |
| US TREASURY N/B | 0.004401 | ✓ |
| US TREASURY N/B | 0.004368 | ✓ |
| US TREASURY N/B | 0.004363 | ✓ |
| US TREASURY N/B | 0.004352 |  |
| US TREASURY N/B | 0.004351 | ✓ |
| US TREASURY N/B | 0.004229 | ✓ |
| US TREASURY N/B | 0.004097 | ✓ |
| FN MA4325 | 0.003869 | ✓ |
| US TREASURY N/B | 0.003867 | ✓ |
| US TREASURY N/B | 0.003849 | ✓ |
| US TREASURY N/B | 0.003815 | ✓ |
| US TREASURY N/B | 0.003774 | ✓ |
| US TREASURY N/B | 0.003721 | ✓ |
| US TREASURY N/B | 0.003697 | ✓ |
| US TREASURY N/B | 0.003684 | ✓ |
| US TREASURY N/B | 0.003658 | ✓ |
| US TREASURY N/B | 0.003624 | ✓ |
| US TREASURY N/B | 0.003524 | ✓ |
| US TREASURY N/B | 0.003515 | ✓ |
| US TREASURY N/B | 0.003507 | ✓ |
| US TREASURY N/B | 0.003500 | ✓ |
| FN MA4255 | 0.003493 | ✓ |
| US TREASURY N/B | 0.003479 | ✓ |
| US TREASURY N/B | 0.003462 | ✓ |
| US TREASURY N/B | 0.003446 | ✓ |
| US TREASURY N/B | 0.003405 | ✓ |
| US TREASURY N/B | 0.003387 | ✓ |
| US TREASURY N/B | 0.003349 | ✓ |

## Fidelity Series Bond Index Fund — top positions

| Security | Weight | Shared |
|----------|--------|--------|
| US TREASURY N/B | 0.011257 | ✓ |
| US TREASURY N/B | 0.010648 | ✓ |
| US TREASURY N/B | 0.009228 | ✓ |
| US TREASURY N/B | 0.008011 | ✓ |
| US TREASURY N/B | 0.007152 | ✓ |
| US TREASURY N/B | 0.006840 | ✓ |
| US TREASURY N/B | 0.006594 | ✓ |
| Fidelity Cash Central Fund | 0.006318 | ✓ |
| US TREASURY N/B | 0.006218 | ✓ |
| US TREASURY N/B | 0.006205 | ✓ |
| US TREASURY N/B | 0.006178 | ✓ |
| Fidelity Securities Lending Cash Central Fund | 0.005920 | ✓ |
| US TREASURY N/B | 0.005903 | ✓ |
| US TREASURY N/B | 0.005772 | ✓ |
| US TREASURY N/B | 0.005443 | ✓ |
| US TREASURY N/B | 0.005260 | ✓ |
| US TREASURY N/B | 0.005202 | ✓ |
| US TREASURY N/B | 0.004961 | ✓ |
| US TREASURY N/B | 0.004954 | ✓ |
| US TREASURY N/B | 0.004949 | ✓ |
| US TREASURY N/B | 0.004926 | ✓ |
| FR SD8121 | 0.004907 | ✓ |
| US TREASURY N/B | 0.004843 | ✓ |
| US TREASURY N/B | 0.004554 | ✓ |
| US TREASURY N/B | 0.004535 | ✓ |
| US TREASURY N/B | 0.004417 | ✓ |
| US TREASURY N/B | 0.004405 | ✓ |
| US TREASURY N/B | 0.004379 | ✓ |
| US TREASURY N/B | 0.004205 | ✓ |
| US TREASURY N/B | 0.004121 | ✓ |
| US TREASURY N/B | 0.003897 | ✓ |
| US TREASURY N/B | 0.003895 | ✓ |
| US TREASURY N/B | 0.003890 | ✓ |
| US TREASURY N/B | 0.003882 | ✓ |
| US TREASURY N/B | 0.003846 |  |
| US TREASURY N/B | 0.003830 | ✓ |
| US TREASURY N/B | 0.003818 | ✓ |
| US TREASURY N/B | 0.003748 | ✓ |
| US TREASURY N/B | 0.003696 | ✓ |
| US TREASURY N/B | 0.003667 | ✓ |
| US TREASURY N/B | 0.003631 | ✓ |
| US TREASURY N/B | 0.003625 | ✓ |
| US TREASURY N/B | 0.003611 |  |
| US TREASURY N/B | 0.003608 | ✓ |
| US TREASURY N/B | 0.003580 | ✓ |
| US TREASURY N/B | 0.003496 | ✓ |
| US TREASURY N/B | 0.003480 | ✓ |
| US TREASURY N/B | 0.003479 | ✓ |
| G2SF 5 3/25 | 0.003405 | ✓ |
| US TREASURY N/B | 0.003367 |  |


## Sources

- N-PORT (fund A) — accession `0000035402-26-002649` (as of 2026-02-28)
  <https://www.sec.gov/Archives/edgar/data/35315/000003540226002649/0000035402-26-002649-index.htm>
- N-PORT (fund B) — accession `0000035402-26-002627` (as of 2026-02-28)
  <https://www.sec.gov/Archives/edgar/data/35315/000003540226002627/0000035402-26-002627-index.htm>

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