ETF comparison
IUSBvsMBB
Both US Aggregate Bond.
Holdings overlap
1,204 positions appear in both funds. Buying equal dollars of IUSB and MBB would leave roughly10.4%of each dollar exposed to the same underlying securities.
Side by side
Sub-score comparison
Tracking quality isn't part of the composite — seewhat we don't scorefor why.
Cost difference
MBB is 2 bps cheaper than IUSB. On a $100,000 position that's about $20/yr more in fees for IUSB.
Fee figure is the annual expense charged on $100,000. To see how the gap compounds over a multi-decade holding period, open thecost calculator pre-filled with IUSB vs MBB.
Top shared holdings
1,204 shared in total| # | Holding | In IUSB | In MBB | Overlap |
|---|---|---|---|---|
| 1 | Government National Mortgage Association | 0.21% | 0.16% | 0.16% |
| 2 | Government National Mortgage Association | 0.11% | 0.30% | 0.11% |
| 3 | Federal Home Loan Mortgage Corp. | 0.10% | 0.12% | 0.10% |
| 4 | Federal National Mortgage Association | 0.10% | 0.33% | 0.10% |
| 5 | Government National Mortgage Association | 0.10% | 0.41% | 0.10% |
| 6 | Federal National Mortgage Association | 0.10% | 0.17% | 0.10% |
| 7 | Federal Home Loan Mortgage Corp. | 0.10% | 0.18% | 0.10% |
| 8 | Government National Mortgage Association | 0.09% | 0.55% | 0.09% |
| 9 | Government National Mortgage Association | 0.09% | 0.53% | 0.09% |
| 10 | Federal National Mortgage Association | 0.09% | 0.13% | 0.09% |
| 11 | Government National Mortgage Association | 0.09% | 0.13% | 0.09% |
| 12 | Federal National Mortgage Association | 0.08% | 0.44% | 0.08% |
Only in IUSB
16,575 total- Blackrock Liquidity Tempcash2.88%
- United States of America0.37%
- United States of America0.37%
- United States of America0.37%
- United States of America0.37%
- United States of America0.36%
- United States of America0.36%
- United States of America0.36%
- United States of America0.35%
- United States of America0.34%
Only in MBB
9,941 total- Government National Mortgage Association0.95%
- UMBS, TBA0.83%
- Government National Mortgage Association0.67%
- UMBS, TBA0.64%
- Government National Mortgage Association0.46%
- Government National Mortgage Association0.36%
- UMBS, TBA0.34%
- Fannie Mae0.33%
- Fannie Mae0.28%
- UMBS, TBA0.26%
Open IUSB or MBB at a brokerage
Both funds trade commission-free at major US brokerages.
Affiliate links — opening an account through these earns PlainIndex a one-time referral. Scoring is computed before any affiliate consideration; see our methodologyand funding disclosure.
Holdings overlap is the sum of min(weight_a, weight_b) over positions matched on ISIN (CUSIP fallback). Methodology: see/methodology/.
Comparing two funds doesn't endorse swapping one for the other. Tax-lot history, account type, and personal goals matter — PlainIndex publishes data and methodology, not investment advice.