

$94.38
TER
0.04%
Low Cost1Y Return
+1.65%
AUM
$38.6B
High LiquidityThe iShares MBS ETF (MBB) seeks to track the investment results of an index composed of investment-grade mortgage-backed pass-through securities issued and/or guaranteed by U.S. government agencies.
Top holdings and sector exposure
BLACKROCK CASH CL INST SL AGENCY
066922519
USD CASH
31288BMZ3
FHLMC 30YR UMBS SUPER
2% · 05/01/2051
GNMA2 30YR TBA(REG C)
5.5% · 06/22/2026
GNMA2 30YR TBA(REG C)
5% · 06/22/2026
UMBS 30YR TBA(REG A)
5% · 06/11/2026
UMBS 30YR TBA(REG A)
5.5% · 06/11/2026
GNMA2 30YR
5% · 11/20/2054
GNMA2 30YR
2% · 10/20/2051
GNMA2 30YR
2% · 12/20/2051
Top holdings and sector exposure
BLACKROCK CASH CL INST SL AGENCY
066922519
USD CASH
31288BMZ3
FHLMC 30YR UMBS SUPER
2% · 05/01/2051
GNMA2 30YR TBA(REG C)
5.5% · 06/22/2026
GNMA2 30YR TBA(REG C)
5% · 06/22/2026
UMBS 30YR TBA(REG A)
5% · 06/11/2026
UMBS 30YR TBA(REG A)
5.5% · 06/11/2026
GNMA2 30YR
5% · 11/20/2054
GNMA2 30YR
2% · 10/20/2051
GNMA2 30YR
2% · 12/20/2051
Learn the fundamentals behind this asset.
An Exchange-Traded Fund is a single tradable share that holds dozens or hundreds of companies inside it. One purchase, one ticker, broad market exposure, and you can buy or sell it during market hours like any stock.
The annual fee a fund charges to manage your money. It sounds tiny on a year-by-year basis. Compounded over decades, it is the single most controllable factor in long-term investment returns.
Diversification is what happens when the things you own do not all rise and fall together. It is the closest thing investing has to a free lunch, but only if you actually buy assets that move differently, not the same asset in five different costumes.
Buy a fixed amount on a fixed schedule, regardless of price. The most-recommended retail investment habit, because it removes the single biggest source of underperformance: timing decisions.