# Portfolio overlap — FIFZX vs IUSB Comparing **Fidelity Series Bond Index Fund** (2026-02-28) and **iShares Core Universal USD Bond ETF** (2026-01-31). - Shared positions: 3797 - Fidelity Series Bond Index Fund covered by iShares Core Universal USD Bond ETF: 0.3283186144860529070372228463 - iShares Core Universal USD Bond ETF covered by Fidelity Series Bond Index Fund: 0.3283186144860529070372228464 ## 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 | | ## iShares Core Universal USD Bond ETF — top positions | Security | Weight | Shared | |----------|--------|--------| | Blackrock Liquidity TempCash Inst | 0.023010 | | | BlackRock Cash Funds: Treasury, SL Agency Shares | 0.007770 | | | US TREASURY N/B | 0.003831 | ✓ | | US TREASURY N/B | 0.003785 | ✓ | | US TREASURY N/B | 0.003777 | ✓ | | US TREASURY N/B | 0.003775 | ✓ | | US TREASURY N/B | 0.003711 | ✓ | | US TREASURY N/B | 0.003708 | ✓ | | US TREASURY N/B | 0.003548 | ✓ | | US TREASURY N/B | 0.003495 | ✓ | | US TREASURY N/B | 0.003432 | ✓ | | US TREASURY N/B | 0.003366 | ✓ | | FN MA4018 | 0.003335 | | | US TREASURY N/B | 0.003275 | ✓ | | US TREASURY N/B | 0.003210 | | | US TREASURY N/B | 0.003197 | ✓ | | US TREASURY N/B | 0.003052 | ✓ | | US TREASURY N/B | 0.002966 | | | US TREASURY N/B | 0.002932 | ✓ | | US TREASURY N/B | 0.002756 | ✓ | | US TREASURY N/B | 0.002756 | ✓ | | US TREASURY N/B | 0.002717 | ✓ | | US TREASURY N/B | 0.002668 | ✓ | | US TREASURY N/B | 0.002655 | ✓ | | US TREASURY N/B | 0.002640 | ✓ | | US TREASURY N/B | 0.002620 | | | US TREASURY N/B | 0.002614 | ✓ | | US TREASURY N/B | 0.002590 | | | US TREASURY N/B | 0.002588 | | | US TREASURY N/B | 0.002547 | | | US TREASURY N/B | 0.002547 | ✓ | | US TREASURY N/B | 0.002473 | ✓ | | US TREASURY N/B | 0.002452 | ✓ | | US TREASURY N/B | 0.002428 | ✓ | | US TREASURY N/B | 0.002422 | ✓ | | US TREASURY N/B | 0.002419 | ✓ | | US TREASURY N/B | 0.002404 | ✓ | | US TREASURY N/B | 0.002394 | | | US TREASURY N/B | 0.002390 | ✓ | | US TREASURY N/B | 0.002343 | ✓ | | US TREASURY N/B | 0.002333 | ✓ | | US TREASURY N/B | 0.002294 | ✓ | | US TREASURY N/B | 0.002260 | ✓ | | US TREASURY N/B | 0.002248 | ✓ | | US TREASURY N/B | 0.002241 | ✓ | | US TREASURY N/B | 0.002226 | ✓ | | US TREASURY N/B | 0.002211 | ✓ | | G2 MA7192 | 0.002184 | ✓ | | US TREASURY N/B | 0.002144 | ✓ | | US TREASURY N/B | 0.002127 | ✓ | ## Sources - N-PORT (fund A) — accession `0000035402-26-002627` (as of 2026-02-28) - N-PORT (fund B) — accession `0002071691-26-007327` (as of 2026-01-31) --- _Informational only — not investment advice. FundWatcher presents publicly available data and makes no recommendation to buy or sell any security. Verify all figures against the source filing before relying on them._ _Data sourced from U.S. SEC EDGAR filings (Forms N-PORT, N-CEN, and prospectus Risk/Return summaries). FundWatcher is not affiliated with the SEC._ _Use of this data is subject to the FundWatcher Terms of Service. Information may be used only for personal, non-commercial research and may not be redistributed. See _