ETF comparison

SPMBvsVMBS

Both US Aggregate Bond.

State Street SPDR Portfolio Mortgage Backed Bond ETF · Vanguard Mortgage-Backed Securities Index Fund ETF Shares

Holdings overlap

Weighted by ISIN/CUSIP
21.2%

805 positions appear in both funds. Buying equal dollars of SPMB and VMBS would leave roughly21.2%of each dollar exposed to the same underlying securities.

SPMB only 77.9%Shared 21.2%VMBS only 78.1%
In SPMB only
1,895 positions
Shared
805 positions
In VMBS only
4,307 positions

Side by side

SPMB

State Street SPDR Portfolio Mortgage Backed Bond ETF

State Street · US Aggregate Bond

86composite / 100
Expense ratio
0.040%
Net assets
$7.14B
TTM yield
4.23%
Top-10 conc.
13.8%
VMBS

Vanguard Mortgage-Backed Securities Index Fund ETF Shares

Vanguard · US Aggregate Bond

89composite / 100
Expense ratio
0.030%
Net assets
$17.59B
TTM yield
4.32%
Top-10 conc.
8.0%

Sub-score comparison

96
Cost
97
52
Tax efficiency
52
94
Liquidity
100
95
Concentration
100
Tracking quality
SPMBsub-scoreVMBS

Tracking quality isn't part of the composite — seewhat we don't scorefor why.

Cost difference

VMBS is 1 bps cheaper than SPMB. On a $100,000 position that's about $10/yr more in fees for SPMB.

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 SPMB vs VMBS.

Top shared holdings

805 shared in total
#HoldingIn SPMBIn VMBSOverlap
1Government National Mortgage Association0.44%0.36%0.36%
2Government National Mortgage Association0.41%0.31%0.31%
3Freddie Mac0.42%0.27%0.27%
4Freddie Mac1.17%0.24%0.24%
5Freddie Mac0.41%0.24%0.24%
6Freddie Mac0.29%0.23%0.23%
7Freddie Mac0.33%0.21%0.21%
8Government National Mortgage Association0.28%0.20%0.20%
9Government National Mortgage Association0.30%0.20%0.20%
10Freddie Mac0.35%0.20%0.20%
11Fannie Mae0.30%0.18%0.18%
12Fannie Mae0.26%0.18%0.18%

Only in SPMB

1,895 total
  • State Street Global Advisors1.03%
  • Fannie Mae0.79%
  • Freddie Mac0.61%
  • Fannie Mae0.49%
  • Fannie Mae0.47%
  • UMBS, TBA0.46%
  • Fannie Mae0.45%
  • Freddie Mac0.44%
  • Freddie Mac0.44%
  • Government National Mortgage Association0.42%

Only in VMBS

4,307 total
  • Fannie Mae or Freddie Mac0.52%
  • Ginnie Mae II Pool0.32%
  • Fannie Mae Pool0.29%
  • Ginnie Mae II Pool0.29%
  • Ginnie Mae II Pool0.29%
  • Ginnie Mae II Pool0.28%
  • Freddie Mac Pool0.27%
  • Freddie Mac Pool0.26%
  • Fannie Mae or Freddie Mac0.25%
  • Fannie Mae or Freddie Mac0.20%

Open SPMB or VMBS 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.