ETF comparison
AGG vs MBB
Both US Aggregate Bond.
Holdings overlap
1,904 positions appear in both funds. Buying equal dollars of AGG and MBB would leave roughly 16.6% of each dollar exposed to the same underlying securities.
Unmatched is the part of a fund's weight the other fund doesn't match: names only it holds, plus any extra weight it puts in names both funds hold.
Side by side
Sub-score comparison
Tracking quality isn't part of the composite — see what we don't score for why.
Cost difference
AGG is 1 bps cheaper than MBB. On a $100,000 position that's about $10/yr more in fees for MBB.
Fee figure is the annual expense charged on $100,000. To see how the gap compounds over a multi-decade holding period, open the cost calculator pre-filled with AGG vs MBB.
Top shared holdings
1,904 shared in total| # | Holding | In AGG | In MBB | Overlap |
|---|---|---|---|---|
| 1 | Fannie Mae | 0.21% | 0.29% | 0.21% |
| 2 | Government National Mortgage Association | 0.20% | 1.05% | 0.20% |
| 3 | UMBS, TBA | 0.17% | 0.70% | 0.17% |
| 4 | Government National Mortgage Association | 0.16% | 0.53% | 0.16% |
| 5 | UMBS, TBA | 0.15% | 0.39% | 0.15% |
| 6 | UMBS, TBA | 0.15% | 0.17% | 0.15% |
| 7 | Government National Mortgage Association | 0.15% | 0.46% | 0.15% |
| 8 | Freddie Mac | 0.13% | 0.17% | 0.13% |
| 9 | Government National Mortgage Association | 0.13% | 0.33% | 0.13% |
| 10 | UMBS, TBA | 0.13% | 0.85% | 0.13% |
| 11 | Fannie Mae | 0.13% | 0.41% | 0.13% |
| 12 | Government National Mortgage Association | 0.13% | 0.22% | 0.13% |
Only in AGG
11,478 total- United States Treasury 0.41%
- United States Treasury 0.40%
- United States Treasury 0.40%
- United States Treasury 0.40%
- United States Treasury 0.39%
- United States Treasury 0.39%
- United States Treasury 0.39%
- United States Treasury 0.38%
- United States Treasury 0.38%
- United States Treasury 0.38%
Only in MBB
9,305 total- Fannie Mae 0.31%
- Fannie Mae 0.26%
- Government National Mortgage Association 0.25%
- Freddie Mac 0.22%
- Fannie Mae 0.21%
- Fannie Mae 0.19%
- Fannie Mae 0.19%
- Fannie Mae 0.18%
- Freddie Mac 0.18%
- Freddie Mac 0.18%
Related comparisons
More comparisons with AGG
- AGG vs FBND · Fidelity Total Bond ETF 16.4%
- AGG vs VGSH · Vanguard Short-Term Treasury Index Fund ETF Shares 15.8%
- AGG vs IEI · iShares 3-7 Year Treasury Bond ETF 15.7%
- AGG vs SHY · iShares 1-3 Year Treasury Bond ETF 15.7%
- AGG vs VCRB · Vanguard Core Bond ETF 15.5%
- AGG vs SPTS · State Street SPDR Portfolio Short Term Treasury Index ETF 15.4%
More comparisons with MBB
- MBB vs SPMB · State Street SPDR Portfolio Mortgage Backed Bond Index ETF 14.9%
- MBB vs EAGG · iShares ESG U.S. Aggregate Bond ETF 12.7%
- MBB vs IUSB · iShares Core Universal USD Bond ETF 9.5%
- MBB vs SCHZ · Schwab U.S. Aggregate Bond ETF 6.9%
- MBB vs SPAB · State Street SPDR Portfolio Aggregate Bond Index ETF 5.8%
- MBB vs BND · Vanguard Total Bond Market Index Fund ETF Shares 5.4%
Percentages are holdings overlap with the named fund.
Open AGG 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 methodology and 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.