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SMBSvsAMUNETF Comparison

ETF 1

SMBS

Schwab Mortgage-Backed Securities ETF

This fund is part of

MBS & ABS

-0.3%

Full SMBS fund page

VS

ETF 2

AMUN

abrdn Ultra Short Municipal Income Active ETF

This fund is part of

Municipal Bonds

-0.42%

Full AMUN fund page

Schwab Mortgage-Backed Securities ETF (SMBS) belongs to the MBS & ABS segment. abrdn Ultra Short Municipal Income Active ETF (AMUN) is part of the Municipal Bonds segment. SMBS's top 3 sector exposures are Industrials, Finance and Government Agencies. In contrast, AMUN's top sector exposures are Municipal and Non-Corporate. SMBS is less expensive with a Total Expense Ratio (TER) of 0.03%, versus 0.74% for AMUN. SMBS is down -0.06% year-to-date (YTD) with +$891M in YTD flows. AMUN performs better with 1.88% YTD performance, and +$25M in YTD flows. Run a side-by-side ETF comparison of SMBS and AMUN below, and assess how they stack up in performance, liquidity, risk, exposure, holdings, and more, helping you select the best ETF for your investments.

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SMBS vs AMUN performance and flow charts

Performance

Cumulative Flows

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Daily, global ETF data for advanced analysis or integration into apps (API), from our partner Trackinsight.

Data Services

Historic performance and flows

Data as of 09/01/2026

		1M	3M	YTD	1Y	3Y	5Y
Perf.	SMBS AMUN	-0.11%+0.24%	-0.85%+0.65%	-0.06%+1.88%	+2.96%n/a	n/an/a	n/an/a
Flows	SMBS AMUN	+$120M+$2M	+$287M+$1M	+$891M+$25M	+$1.28B-	--	--

Volatility and drawdown

		3M	1Y	3Y	5Y
Volatility	SMBS AMUN	+4.44%+0.34%	+3.94%n/a	n/an/a	n/an/a
Max drawdown	SMBS AMUN	-1.75%-0.03%	-2.67%n/a	n/an/a	n/an/a
Max drawdown duration	SMBS AMUN	64d2d	184dn/a	n/an/a	n/an/a

Trading data

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	SMBS	AMUN
Last sale 9/2/2026 at 1:30 PM	$24.79	$26.04
Previous close 09/01/2026	$24.78	$26.04
Consolidated volume 09/01/2026
Average volume 30 days
Average discount or premium 30 days
Average Bid/Ask spread 30 days

Replication quality

Data as of August 31, 2026

1-year trailing difference

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AMUN

is actively managed and doesn’t replicate an index

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	SMBS	AMUN
Tracking error
Tracking difference
1 year cumulative return difference
Best
Worst
Daily return difference
Average
Worst

Main metrics

Last update 9/2/2026 at 1:30 PM

Live

Closed

	SMBS	AMUN
Last price	$24.79	$26.04
1D performance	+0.06%	+0.02%
AuM	$6.53 B	$55.04 M
E/R	0.03%	0.74%

Characteristics

	SMBS	AMUN
Management strategy	Passive	Active
Provider	Schwab ETFs	abrdn
Benchmark	Bloomberg U.S. MBS Float Adjusted Index	-
N° of holdings	443	17
Asset class	Bonds	-
Trailing 12m distribution yield	Join	Join
Inception date	November 19, 2024	October 17, 2025
ESG	No	No

More SMBS data on Trackinsight

More AMUN data on Trackinsight

Exposure

Countries

SMBS

USA

34%

Other

66%

AMUN

USA

33.29%

Other

66.71%

Sectors

SMBS

Industrials

33.45%

Other

66.55%

AMUN

Municipal

33.11%

Other

66.89%

Diversification

SMBS

Total weight of top 15 holdings out of 15

5.64%

AMUN

Total weight of top 15 holdings out of 15

53.8%

Top 15 holdings

Data as of July 31, 2026

SMBS

G2 MB0025, 5% 20nov2054, USD (ABS)

0.67%

FR SD8469, 5.5% 1oct2054, USD (ABS)

0.49%

US31418DYX47

0.40%

US31427R6E50

0.39%

FR SD8193, 2% 1feb2052, USD (ABS)

0.37%

FR SD8106, 2% 1nov2050, USD (ABS)

0.35%

US3618N6HU47

0.35%

US3618N56H72

0.35%

US3618N53X59

0.35%

FR RQ0110, 5% 1apr2056, USD (ABS)

0.34%

FR RQ0102, 5% 1mar2056, USD (ABS)

0.34%

US3132DWDC47

0.33%

FR SD7552, 2.5% 1jan2052, USD (ABS)

0.31%

US3142J6BK85

0.30%

US3132DWAN39

0.30%

AMUN

Massachusetts Port Authority, 5% 1jul2043, USD (2016-B)

4.70%

Tennessee Energy Acquisition Corp., 5.625% 1sep2026, USD

4.14%

US46640KYU23

4.13%

US546598AA16

3.95%

US230589AB90

3.81%

Chandler Industrial Development Authority, 5% 1sep2052, USD (2022-2)

3.79%

Newark, 4.25% 5may2027, USD (2026)

3.77%

US478232SD45

3.77%

US88035TZV50

3.76%

US34074EAF60

3.76%

US7386297S79

3.75%

Mississippi Business Finance Corp., FRN 1nov2032, USD (2007A)

3.08%

US414008CX87

2.77%

PEFA Inc., 5% 1sep2049, USD (2019)

2.35%

US06964KAB26

2.26%

Frequently asked questions about SMBS and AMUN

How have the SMBS and AMUN ETFs performed in 2026?

As of September 1, 2026, SMBS is down -0.06% year-to-date (YTD), while AMUN has returned 1.88%. That puts AMUN better performer ahead so far this year.

Which ETF is attracting more investor money: SMBS or AMUN?

Year-to-date, the SMBS ETF saw +$891M in flows, compared to +$25M for AMUN.

Which ETF is bigger: SMBS or AMUN?

As of September 1, 2026, SMBS holds $6.53 B in assets under management (AUM), while AMUN manages $55.04 M.

What sectors do the SMBS and AMUN ETFs invest in?

SMBS leans toward sectors like Industrials. Meanwhile, AMUN focuses on Municipal.

What are the top holdings of the SMBS ETF and AMUN ETF?

SMBS top holdings include G2 MB0025, 5% 20nov2054, USD (ABS), FR SD8469, 5.5% 1oct2054, USD (ABS) and US31418DYX47. AMUN holds in its top three: Massachusetts Port Authority, 5% 1jul2043, USD (2016-B), Tennessee Energy Acquisition Corp., 5.625% 1sep2026, USD and US46640KYU23.

SMBSvsAMUNETF Comparison

Schwab Mortgage-Backed Securities ETF

abrdn Ultra Short Municipal Income Active ETF

SMBS vs AMUN performance and flow charts

Performance

Cumulative Flows

Get all the metrics on this page, and more, through a reliable ETF data feed

Countries

Sectors

Diversification

Top 15 holdings

How have the SMBS and AMUN ETFs performed in 2026?

As of September 1, 2026, SMBS is down -0.06% year-to-date (YTD), while AMUN has returned 1.88%. That puts AMUN better performer ahead so far this year.

Which ETF is attracting more investor money: SMBS or AMUN?

Year-to-date, the SMBS ETF saw +$891M in flows, compared to +$25M for AMUN.

Which ETF is bigger: SMBS or AMUN?

As of September 1, 2026, SMBS holds $6.53 B in assets under management (AUM), while AMUN manages $55.04 M.

What sectors do the SMBS and AMUN ETFs invest in?

SMBS leans toward sectors like Industrials. Meanwhile, AMUN focuses on Municipal.

What are the top holdings of the SMBS ETF and AMUN ETF?

SMBS top holdings include G2 MB0025, 5% 20nov2054, USD (ABS), FR SD8469, 5.5% 1oct2054, USD (ABS) and US31418DYX47. AMUN holds in its top three: Massachusetts Port Authority, 5% 1jul2043, USD (2016-B), Tennessee Energy Acquisition Corp., 5.625% 1sep2026, USD and US46640KYU23.

Which ETF is more diversified: SMBS or AMUN?

SMBS holds 1999 securities with 5.64% of its assets in the top 15. AMUN has 63 securities and a top 15 weight of 53.8%.

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