Which resets first, CPST or GSEP?

CPST ends its outcome period on Sep 1, 2027 and GSEP on Sep 17, 2027. A new cap is set the day after each.

Which is cheaper, CPST or GSEP?

CPST charges 0.69% a year and GSEP charges 0.85%, so CPST is cheaper. Fees come from each fund's prospectus.

CPST vs GSEP: which one stands where?

As of Oct 1, 2026 GSEP can fall 1.0% before its buffer engages and CPST 0.1%, and CPST resets 17 days sooner. Calamos S&P 500 ® Structured Alt Protection ETF - September and FT Vest U.S. Equity Moderate Buffer ETF - September.

CPSTFull floor

CPST: reference +0.1% since period start, fund 0.0%; buffer −0 to floor; cap +8.0%; Full floor.

GSEPBetween buffer and cap

GSEP: reference +0.1% since period start, fund +0.2%; buffer 0 to −15; cap +14.1%; Between buffer and cap.

These are two different products. CPST is a floor fund, which caps how far a holder can fall. GSEP 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 Sep 1, 2027, 335 days from now; GSEP runs to Sep 17, 2027, 352 days. A fall from here reaches CPST’s buffer after 0.1% and GSEP’s after 1.0%. 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

	Total return		Gap to the reference
Window	CPST	GSEP	CPST	GSEP
3 months	+1.0%	+2.8%	−1.5 pts	+0.3 pts
6 months	+3.9%	+10.2%	−13.0 pts	−6.8 pts
1 year	+5.2%	+10.6%	−10.5 pts	−5.1 pts
3 years	not published	+42.5%	not published	−42.5 pts

CPST and GSEP over each window. Every figure is an ETFIQ calculation with distributions reinvested. Source: ETFIQ. Open the live comparison on ETFIQ →

On the same fields

CPST

Calamos S&P 500 ® Structured Alt Protection ETF - September · Absorbs losses from 0.0% to 100.0% on SPY and caps the gain at 8.0%, over a period ending Sep 1, 2027

GSEP

FT Vest U.S. Equity Moderate Buffer ETF - September · Absorbs the first 0% to 15% of loss on SPY and caps the gain at 14.1%, over a period ending Sep 17, 2027

Issuer Calamos First Trust

Reference index SPY SPY

Buffer 0% to 100% 0% to 15%

Outcome period Sep 1, 2026 to Sep 1, 2027 Sep 21, 2026 to Sep 17, 2027

Days left 335 352

Starting cap +8.0% +14.1%

Can still gain not published 13.1%

Fall before buffer 0.1% 1.0%

Protection left, index points 100.0% of 100.0% 15.0% of 15.0%

Index return this period +0.1% +0.1%

Fund return this period 0.0% +0.2%

State today Open Open

Expense ratio 0.69% 0.85%

Net assets $37m $359m

CPST and GSEP on the same fields, as of Oct 1, 2026. Source: ETFIQ.

CPST in plain words

The fund's price can fall 0.1% from here before the buffer starts absorbing losses, by the issuer's figure. In index terms, SPY can fall 0.1% 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. 335 days remained on Oct 1, 2026. On Sep 1, 2027 the period ends and a new cap is set.

GSEP in plain words

From its price on Oct 1, 2026, the fund can gain about 13.1% more before it reaches its cap. The fund's price can fall 1.0% from here before the buffer starts absorbing losses, by the issuer's figure. Protection left, in index points: 15.0% of the 15.0% buffer still sits below today's SPY level. 352 days remained on Oct 1, 2026. On Sep 17, 2027 the period ends and a new cap is set.

Questions people ask

Which resets first, CPST or GSEP?: CPST ends its outcome period on Sep 1, 2027 and GSEP on Sep 17, 2027. A new cap is set the day after each.
Which is cheaper, CPST or GSEP?: CPST charges 0.69% a year and GSEP charges 0.85%, so CPST is cheaper. Fees come from each fund's prospectus.

Other comparisons

CPST vs QBSV CPST vs SEPM CPST vs SEPP CPST vs SEPT GSEP vs OCTP GSEP vs OCTT GSEP vs OCTU GSEP vs OCTW

S&P 500 (SPY) →CPST on its own →GSEP on its own →How every figure is computed →Standards and sources →

Where these figures came from

CPST filings on SEC EDGAR ↗Calamos website ↗GSEP filings on SEC EDGAR ↗First Trust page for GSEP ↗

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

Cite this page

ETFIQ, CPST against GSEP, data as of Oct 1, 2026. https://etfiq.com/compare/buffer/cpst-vs-gsep

Open data

Free to use with attribution. Every figure is calculated from a named public source; the method is at etfiq.com/methodology.