iShares Mortgage-Backed Securities Active ETF

iShares Mortgage-Backed Securities Active ETF

About

iShares Mortgage-Backed Securities Active ETF (US0925287932) is a US-listed bond ETF tracking the Bloomberg U.S. MBS Index. With a expense ratio of 0.25%, it is moderately priced, paying distributions. The fund holds 523 positions across 1 region with 153M in assets.

Score Breakdown

Scores are scaled 1–10 on a logarithmic curve relative to all ETFs in the database. Last updated: Jun 22, 2026
Component Score Details
Cost (30%) 8.4 Tracking Difference: 10.0 · TD Consistency: — · Expense Ratio: 4.6
Liquidity (25%) 6.1 Assets Under Management

Data sources: provider factsheets, exchange data, and NAV history. Information for educational purposes only — not investment advice.

Ticker MBBA
ISIN
Fund Size $152.9M
Issuer iShares
Distribution Pays Distributions
Replication Physical
Inception May 1998
Base Currency USD
Index Bloomberg U.S. MBS Index
Asset Class Bonds
Category Securitized Bond

Costs

8.4
This fund has low total costs, with competitive tracking and expense ratios.

Cost Metrics Explained

What expense ratio, tracking difference, and TD consistency measure

Expense ratio (Total Expense Ratio) is the annual fee the fund charges, deducted from assets. It’s the headline cost, but not the full picture.

Tracking Difference measures how much the fund actually lags (or leads) its benchmark index per year. This is the single best measure of true cost — it captures the expense ratio plus all other drags like sampling error and tax withholding. A lower (or negative) value is better.

TD Consistency measures how stable the tracking difference is from year to year. A low value means predictable, reliable costs; a high value means costs can vary significantly.
Expense Ratio0.00%
 
Metric Value
Expense Ratio 0.25%

Cumulative Returns

Performance across different time periods.
Year to Date+0.00%
1 Year+0.00%
3 Years+0.00%
5 Years+0.00%
Inception+0.00%
 
Period Cumulative Return
1 Month —
3 Months —
6 Months —
1 Year +7.23%
3 Years +4.43%
5 Years +0.25%
10 Years +1.26%
YTD +0.96%
Since Inception +3.84%

Holdings

This fund invests into 523 individual investments.
#1
BLACKROCK LIQ FUND T-FD-IN
15.09%
#2
UMBS 30YR TBA(REG A)
11.97%
#3
UMBS 30YR TBA(REG A)
11.67%
#4
UMBS 30YR TBA(REG A)
11.04%
#5
Fannie Mae Pool
9.38%
#6
GNMA2 30YR TBA(REG C)
7.11%
#7
UMBS 15YR TBA(REG B)
4.42%
#8
FHSTR_454 DA
3.59%
#9
GNMA2 30YR TBA(REG C)
3.37%
#10
FNMA 30YR UMBS SUPER
2.83%
View all holdings (50)
# Holding Ticker Weight
1 BLACKROCK LIQ FUND T-FD-IN TSTXX 1509.16%
2 UMBS 30YR TBA(REG A) UM30 1197.33%
3 UMBS 30YR TBA(REG A) UM30 1167.16%
4 UMBS 30YR TBA(REG A) UM30 1103.83%
5 Fannie Mae Pool FNMA6053 938.21%
6 GNMA2 30YR TBA(REG C) G230J 710.73%
7 UMBS 15YR TBA(REG B) UM15 442.16%
8 FHSTR_454 DA FHSTR_454-DA 358.52%
9 GNMA2 30YR TBA(REG C) G230J 336.84%
10 FNMA 30YR UMBS SUPER FNFS1538 282.98%
11 UMBS 30YR TBA(REG A) UM30 237.54%
12 Ginnie Mae II Pool G230J 217.86%
13 GNMA2 30YR TBA(REG C) G230J 198.56%
14 GNMA_15-55 A GNMA_15-55-A 191.39%
15 FNMA 30YR UMBS SUPER FNFS8474 190.79%
16 GNMA2 30YR TBA(REG C) G230J 165.77%
17 GNMA 30YR PLATINUM GN784176 162.84%
18 FHLMC 30YR UMBS SUPER FRSD6472 157.12%
19 GNMA_20-149H IA GNMA_20-149H-IA 153.22%
20 FNMA 30YR UMBS SUPER FNFS4974 151.59%
21 FNMA 30YR UMBS SUPER FNFA3656 144.73%
22 GNMA2 30YR 3.0 MBS-TBA 7/26 G230J 142.79%
23 FHLMC_5052 KI FHLMC_5052-KI 121.15%
24 UMBS 30YR TBA(REG A) UM30 109.64%
25 UMBS 30YR TBA(REG A) UM30 107.16%
26 FHLMC 30YR UMBS SUPER FRSL3074 99.47%
27 UMBS 15YR TBA(REG B) UM15 98.48%
28 UMBS 15YR TBA(REG B) UM15 95.21%
29 FHLMC 30YR UMBS SUPER FRSL0236 89.33%
30 FNMA 30YR UMBS FNMA4761 89.21%
31 FNMA 30YR UMBS FNCB6329 86.99%
32 Ginnie Mae II Pool G2MA6409 85.96%
33 FHLMC 30YR UMBS FRSL5575 85.61%
34 GNMA_23-130P OD GNMA_23-130P-OD 85.17%
35 GNMA 30YR GN783848 80.89%
36 FNMA 30YR UMBS SUPER FNFA0446 78.86%
37 GNMA_22-127C IA GNMA_22-127C-IA 77.82%
38 FNMA 30YR UMBS FNFA5986 75.35%
39 GNMA2 30YR G2DA2517 73.82%
40 GNMA_21-159 IH GNMA_21-159-IH 72.49%
41 Freddie Mac Pool FRSD8289 72.24%
42 FHLMC 30YR UMBS SUPER FRSD6225 71.72%
43 FHLMC 30YR UMBS FRSD0478 70.28%
44 FNMA 30YR UMBS FNCB6757 70.06%
45 GNMA2 30YR G2BD6187 69.88%
46 UMBS 30YR TBA(REG A) UM30 69.79%
47 GNMA2 30YR G2DI1009 63.38%
48 FHLMC 30YR UMBS SUPER FRSL0006 62.44%
49 FNMA 30YR UMBS FNBY0350 61.92%
50 GNMA2 30YR G2CW7310 61.51%

Sectors

Allocation by industry sector.
 
Sector Weight
Unknown 9084.00%
Securitized Bonds 2489.00%

Regions

Geographic allocation by country of risk.
 
Country Weight
UNKNOWN 5938.00%
United States 4062.00%

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