MBB vs SPMB
iShares MBS ETF vs State Street SPDR Portfolio Mortgage Backed Bond ETF
Which is better, MBB or SPMB?
MBB has been ahead.
MBB led over 1Y, 3Y, 5Y and the full window. The two have moved almost in lockstep, correlation 0.96.
MarketXLS is not an investment adviser. This comparison is generated automatically from market data and is for information only. A Best mark means the better reading on that one measure, not a recommendation to buy.
Side-by-Side Comparison
| Metric | MBB | SPMB |
|---|---|---|
| Expense Ratio | 0.04%Tie | 0.04%Tie |
| AUM | $35.7B | $6.8B |
| Dividend Yield | 4.51% | 4.33% |
| Holdings | 22,427 | 2,741 |
| YTD Return | -2.28% | -2.27%Best |
| 1Y Return | -1.64%Best | -1.70% |
| 3Y Return (annualized) | +5.22%Best | +5.18% |
| 5Y Return (annualized) | -0.25%Best | -0.26% |
| Volatility (annualized) | 4.3%Best | 4.6% |
| Max Drawdown | -18.4%Best | -22.8% |
| $10,000 over 5 years | $9,876Best | $9,871 |
| Fund Family | iShares by BlackRock (US) | State Street Investment Management |
| Category | Fixed Income | Fixed Income |
| Inception | Mar 13, 2007 | Jan 15, 2009 |
Not shown on this pair: Top 10 Weight, Style.
Volatility and max drawdown are measured over the window both funds cover: Jan 27, 2009 to Oct 14, 2026 (17.7 years).
MBB vs SPMB growth
Month-end closes. Both lines start at 0% in the first month shown, so the gap between them is the difference in growth across that window. The full view covers the 17.7 years both funds cover.
MBB vs SPMB Performance
iShares MBS ETF (MBB) is an ETF from iShares by BlackRock (US) and State Street SPDR Portfolio Mortgage Backed Bond ETF (SPMB) is an ETF from State Street Investment Management. Over the past year MBB returned -1.64% while SPMB returned -1.70%. Year to date, MBB is down 2.28% versus a loss of 2.27% for SPMB.
Over three years, MBB compounded at +5.22% per year against +5.18% for SPMB; over five years the annualized figures are -0.25% and -0.26% respectively. Across the full 18-year window we track, MBB has the edge at +0.15% annualized vs -0.03%.
Past performance does not guarantee future results.
Risk: Volatility and Drawdowns
SPMB has been the more volatile fund, with annualized monthly volatility of 4.6% compared with 4.3% for MBB. Lower volatility generally means a smoother ride, though it often comes with lower long-run returns.
The deepest peak-to-trough decline in our data was -18.4% for MBB and -22.8% for SPMB. Drawdown depth is what each fund did in the worst stretch of the window measured above.
The two funds' monthly returns correlate at 0.96. They move almost in lockstep, so holding both mostly duplicates the same exposure.
Fees and Cost Over Time
MBB charges 0.04% per year while SPMB charges 0.04%. On a $10,000 position that is $4 vs $4 annually. On income, MBB currently yields 4.51% against 4.33% for SPMB.
Holdings Overlap
We hold position weights for 7,997 holdings in MBB and 2,450 in SPMB, totalling 86.0% and 81.5% of the two funds. Neither is a share of a fund we can divide by, so no overlap percentage is shown here. Within what we can see, 755 positions appear in both.
755 positions in common, counted across the 7,997 positions we hold weights for in MBB and 2,450 in SPMB, against full books of 22,427 and 2,741.
Top Shared Holdings
| Stock | Weight in MBB | Weight in SPMB | Difference |
|---|---|---|---|
| FNCL 5.5 10/11Fannie Mae Or Freddie Mac 2050-10-01 | 0.60% | 1.34% | 0.74% |
| G2SF 6 10/11Ginnie Mae 6 | 0.68% | 0.28% | 0.40% |
| FNCL 5 10/11Fncl 5 10/26 | 0.35% | 0.54% | 0.19% |
| G2SF 5.5 10/11Government National Mortgage Association | 0.57% | 0.31% | 0.26% |
| FN MA4465Fannie Mae 2051-11-01 | 0.44% | 0.43% | 0.01% |
| FN MA4547Fannie Mae Pool Umbs P#Ma4547 2.00000000 | 0.08% | 0.71% | 0.63% |
| FR SD8140Freddie Mac 2 04/01/2051 | 0.50% | 0.27% | 0.23% |
| G2 MA7766Gnma2 30Yr 2% Dec 20, 2051 | 0.53% | 0.18% | 0.35% |
| FN MA4437Fannie Mae Pool Umbs P#Ma4437 2.00000000 | 0.31% | 0.34% | 0.03% |
| FNCL 6 10/11Fannie Mae Or Freddie Mac 6 | 0.27% | 0.38% | 0.11% |
You are not choosing between two funds in isolation.
Whichever of MBB and SPMB you pick has to sit alongside everything else you own. Add the rest and see what the combination actually holds.
Free for up to 10 holdings. No account needed.
Frequently Asked Questions
Which is cheaper, MBB or SPMB?
MBB has an expense ratio of 0.04% while SPMB charges 0.04%. At the precision these are quoted to, they cost the same.
Which performed better, MBB or SPMB?
Over the past year MBB returned -1.64% vs -1.70% for SPMB, so MBB leads on 1-year performance. Over the longest common window we track (18 years), MBB annualized +0.15% vs -0.03% for SPMB. Past performance does not guarantee future results. This is information, not a recommendation.
Which is riskier, MBB or SPMB?
SPMB has been the more volatile fund at 4.6% annualized versus 4.3% for MBB. Worst drawdown: MBB -18.4% vs SPMB -22.8%.
Should I hold both MBB and SPMB?
MBB and SPMB have a monthly-return correlation of 0.96, so they move almost identically. What is left to separate them is the fee and the index each one tracks. This is information, not a recommendation.
Which pays a higher dividend, MBB or SPMB?
MBB yields 4.51% while SPMB yields 4.33%, so MBB currently pays the higher dividend yield.
Is SPMB better than MBB?
MBB led over 1Y, 3Y, 5Y and the full window. The two have moved almost in lockstep, correlation 0.96. Which one suits a particular account depends on what it is for. This is information, not a recommendation.