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Data as of .

CPST vs SEPW: which one stands where?

As of Sep 21, 2026 SEPW can fall 1.2% before its buffer engages and CPST 0.2%, and CPST resets 1 days sooner.

Calamos S&P 500 ® Structured Alt Protection ETF - September and AllianzIM U.S. Equity Buffer20 ETF - Sep.

CPSTBuffer working
full floor beneathfull floor0% period start+8.0% capTODAY · SPY 0.0%full floor beneathfull floor0% start+8.0% capTODAY · SPY 0.0%
SEPWBetween buffer and cap
20 pts of buffer−20.0% floor0% period start+12.3% capTODAY · SPY +0.9%−20.0% floor0% start+12.3% capTODAY · SPY +0.9%

These are two different products. CPST is a floor fund, which caps how far a holder can fall. SEPW is a buffer fund, which absorbs the first part of a fall and leaves everything below it with the holder.

Where each one stands today

CPST resets first, on Aug 31, 2027, 344 days from now; SEPW runs to Aug 31, 2027, 345 days. A fall from here reaches CPST’s buffer after 0.2% and SEPW’s after 1.2%. Both track SPY, so what separates them is where each is in its own period.

Every figure is ETFIQ’s own, from the issuer’s published outcome-period terms. A buffer ETF holds FLEX options on its reference index rather than shares, so there is no holdings overlap between two of them to report.

Performance, window by window

CPST and SEPW over each window. Every figure is an ETFIQ calculation with distributions reinvested. Source: ETFIQ.
WindowTotal returnGap to the reference
CPSTSEPWCPSTSEPW
3 months+1.1%+1.6%−1.2 pts−0.7 pts
6 months+4.1%+7.5%−14.0 pts−10.6 pts
1 year+5.0%+8.2%−11.6 pts−8.3 pts
3 yearsnot published+35.9%not published−42.5 pts
Open the live comparison on ETFIQ
CPST and SEPW on the same fields, as of Sep 21, 2026. Source: ETFIQ.
CPST
Calamos S&P 500 ® Structured Alt Protection ETF - September
Absorbs the whole loss on SPY and caps the gain at 8.0%, over a period ending Aug 31, 2027
SEPW
AllianzIM U.S. Equity Buffer20 ETF - Sep
Absorbs the first 20% of loss on SPY and caps the gain at 12.3%, over a period ending Aug 31, 2027
IssuerCalamosAllianzIM
Reference indexSPYSPY
Buffer100%20%
Outcome periodSep 1, 2026 to Aug 31, 2027Sep 1, 2026 to Aug 31, 2027
Days left344345
Starting cap+8.0%+12.3%
Can still gainnot published11.1%
Fall before buffer0.2%1.2%
Protection left, index points100.0% of 100.0%20.0% of 20.0%
Index return this period0.0%+0.9%
Fund return this period+0.1%+0.5%
State todayBuffer workingOpen
Expense ratio0.69%0.74%
Net assets$37m$123m

CPST in plain words

The fund's price can fall 0.2% from here before the buffer starts absorbing losses, by the issuer's figure. In index terms, SPY can fall 0.0% from today's level to the point where the buffer begins. Protection left, in index points: 100.0% of the 100.0% buffer still sits below today's SPY level. 344 days remained on Sep 21, 2026. On Aug 31, 2027 the period ends and a new cap is set.

SEPW in plain words

From its price on Sep 21, 2026, the fund can gain about 11.1% more before it reaches its cap. The fund's price can fall 1.2% from here before the buffer starts absorbing losses, by the issuer's figure. In index terms, SPY can fall 0.9% from today's level to the point where the buffer begins. Protection left, in index points: 20.0% of the 20.0% buffer still sits below today's SPY level. 345 days remained on Sep 21, 2026.

Questions people ask

Which resets first, CPST or SEPW?
CPST ends its outcome period on Aug 31, 2027 and SEPW on Aug 31, 2027. A new cap is set the day after each.
Which is cheaper, CPST or SEPW?
CPST charges 0.69% a year and SEPW charges 0.74%, so CPST is cheaper. Fees come from each fund's prospectus.

Other comparisons

Where these figures came from

ETFIQ links to the documents behind every figure. It is not affiliated with any issuer, and a link is not an endorsement.

CPST against SEPW, ETFIQ, data as of Sep 21, 2026. Every figure is calculated from a named public source; the method is at etfiq.com/methodology. A comparison is not a recommendation.

Cite this page. ETFIQ, CPST against SEPW, data as of Sep 21, 2026. https://etfiq.com/compare/buffer/cpst-vs-sepw Free to use with attribution; the underlying files are at Open data.

How every figure is computed · Standards and sources