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Data as of .

CPST vs ZSEP: which one stands where?

As of Sep 21, 2026 ZSEP can fall 0.3% before its buffer engages and CPST 0.2%.

Calamos S&P 500 ® Structured Alt Protection ETF - September and Innovator Equity Defined Protection ETF - 1 Yr September.

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%
ZSEPFull floor
full floor beneathfull floor0% period start+8.9% capTODAY · SPY +0.9%full floor beneathfull floor0% start+8.9% capTODAY · SPY +0.9%

Where each one stands today

CPST resets first, on Aug 31, 2027, 344 days from now; ZSEP runs to Aug 31, 2027, 344 days. A fall from here reaches CPST’s buffer after 0.2% and ZSEP’s after 0.3%. 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 ZSEP over each window. Every figure is an ETFIQ calculation with distributions reinvested. Source: ETFIQ.
WindowTotal returnGap to the reference
CPSTZSEPCPSTZSEP
3 months+1.1%+1.2%−1.2 pts−1.1 pts
6 months+4.1%+4.3%−14.0 pts−13.7 pts
1 year+5.0%+4.9%−11.6 pts−11.6 pts
Open the live comparison on ETFIQ
CPST and ZSEP 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
ZSEP
Innovator Equity Defined Protection ETF - 1 Yr September
Absorbs the whole loss on SPY and caps the gain at 8.9%, over a period ending Aug 31, 2027
IssuerCalamosInnovator
Reference indexSPYSPY
Buffer100%100%
Outcome periodSep 1, 2026 to Aug 31, 2027Aug 31, 2026 to Aug 31, 2027
Days left344344
Starting cap+8.0%+8.9%
Can still gainnot published8.5%
Fall before buffer0.2%0.3%
Protection left, index points100.0% of 100.0%100.0% of 100.0%
Index return this period0.0%+0.9%
Fund return this period+0.1%+0.3%
State todayBuffer workingOpen
Expense ratio0.69%0.79%
Net assets$37m$220m

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.

ZSEP in plain words

From its price on Sep 21, 2026, the fund can gain about 8.5% more before it reaches its cap. The fund's price can fall 0.3% 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.

Questions people ask

Which resets first, CPST or ZSEP?
CPST ends its outcome period on Aug 31, 2027 and ZSEP on Aug 31, 2027. A new cap is set the day after each.
Which is cheaper, CPST or ZSEP?
CPST charges 0.69% a year and ZSEP charges 0.79%, 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 ZSEP, 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 ZSEP, data as of Sep 21, 2026. https://etfiq.com/compare/buffer/cpst-vs-zsep Free to use with attribution; the underlying files are at Open data.

How every figure is computed · Standards and sources