# Portfolio overlap — FNDSX vs FIFZX

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

- Shared positions: 2382
- Fidelity Sustainability Bond Index Fund covered by Fidelity Series Bond Index Fund: 0.5119406357350648396298210036
- Fidelity Series Bond Index Fund covered by Fidelity Sustainability Bond Index Fund: 0.5119406357350648396298210034

## Fidelity Sustainability Bond Index Fund — top positions

| Security | Weight | Shared |
|----------|--------|--------|
| US TREASURY N/B | 0.021359 |  |
| US TREASURY N/B | 0.012976 | ✓ |
| Fidelity Cash Central Fund | 0.012516 | ✓ |
| US TREASURY N/B | 0.009316 | ✓ |
| US TREASURY N/B | 0.008968 | ✓ |
| US TREASURY N/B | 0.007948 | ✓ |
| US TREASURY N/B | 0.007338 | ✓ |
| US TREASURY N/B | 0.007194 | ✓ |
| US TREASURY N/B | 0.006813 | ✓ |
| US TREASURY N/B | 0.006726 | ✓ |
| US TREASURY N/B | 0.006624 | ✓ |
| US TREASURY N/B | 0.006541 | ✓ |
| US TREASURY N/B | 0.005905 | ✓ |
| US TREASURY N/B | 0.005704 | ✓ |
| US TREASURY N/B | 0.005509 | ✓ |
| US TREASURY N/B | 0.005477 | ✓ |
| US TREASURY N/B | 0.005467 | ✓ |
| US TREASURY N/B | 0.005366 | ✓ |
| US TREASURY N/B | 0.005251 | ✓ |
| US TREASURY N/B | 0.004939 | ✓ |
| US TREASURY N/B | 0.004874 | ✓ |
| US TREASURY N/B | 0.004851 | ✓ |
| US TREASURY N/B | 0.004708 | ✓ |
| US TREASURY N/B | 0.004697 | ✓ |
| US TREASURY N/B | 0.004691 | ✓ |
| US TREASURY N/B | 0.004631 | ✓ |
| US TREASURY N/B | 0.004441 |  |
| US TREASURY N/B | 0.004405 | ✓ |
| US TREASURY N/B | 0.004363 | ✓ |
| US TREASURY N/B | 0.004243 | ✓ |
| US TREASURY N/B | 0.004215 | ✓ |
| US TREASURY N/B | 0.003988 | ✓ |
| US TREASURY N/B | 0.003983 | ✓ |
| US TREASURY N/B | 0.003902 | ✓ |
| US TREASURY N/B | 0.003865 | ✓ |
| US TREASURY N/B | 0.003841 | ✓ |
| US TREASURY N/B | 0.003834 |  |
| US TREASURY N/B | 0.003800 | ✓ |
| US TREASURY N/B | 0.003780 | ✓ |
| US TREASURY N/B | 0.003774 |  |
| US TREASURY N/B | 0.003741 | ✓ |
| US TREASURY N/B | 0.003713 | ✓ |
| US TREASURY N/B | 0.003646 | ✓ |
| US TREASURY N/B | 0.003644 |  |
| FN MA4208 | 0.003514 | ✓ |
| US TREASURY N/B | 0.003495 | ✓ |
| US TREASURY N/B | 0.003390 | ✓ |
| US TREASURY N/B | 0.003388 | ✓ |
| US TREASURY N/B | 0.003380 | ✓ |
| G2SF 5 3/25 | 0.003329 | ✓ |

## 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 `0000035402-26-002631` (as of 2026-02-28)
  <https://www.sec.gov/Archives/edgar/data/35315/000003540226002631/0000035402-26-002631-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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