CPST vs ZSEP: Cap, Buffer & Days Left
As of Oct 13, 2026 ZSEP can fall 0.8% before its buffer engages and CPST 0.5%. Net assets on Oct 12, 2026: $41m for Calamos S&P 500 ® Structured Alt Protection ETF - September and $237m for Innovator Equity Defined Protection ETF - 1 Yr September.
CPST costs 0.10 points a year less; their one-year returns differ by 0.4 points; ZSEP is 5.8 times larger.
Points (pts) are percentage points.
| CPST | ZSEP | |
|---|---|---|
| Expense ratio | 0.69% | 0.79% |
| Net assets, as of Oct 12, 2026 | $41m | $237m |
| Total return, 1 year | +5.7% | +6.1% |
| What it tracks | SPY | SPY |
| Holdings in common | not published | |
| Index fall to the buffer | 2.1% | 1.3% |
CPST: reference +2.1% since period start, fund +0.5%; buffer Floor; cap +8.1%; Full floor. Figures to Oct 13, 2026.
Figures to Oct 13, 2026.
ZSEP: reference +1.3% since period start, fund +0.7%; buffer Floor; cap +8.9%; Full floor. Figures to Oct 13, 2026.
Figures to Oct 13, 2026.
Where each one stands today
CPST resets first, on Aug 31, 2027, 322 days from now; ZSEP runs to Aug 31, 2027, 322 days. A fall from here reaches CPST’s buffer after 0.5% and ZSEP’s after 0.8%. Both track SPY, so what separates them is where each is in its own period.
Performance, window by window
| Total return | Gap to the reference's price return | |||
|---|---|---|---|---|
| Window | CPST | ZSEP | CPST | ZSEP |
| 3 months | +1.3% | +1.4% | −2.6 pts | −2.5 pts |
| 6 months | +3.4% | +3.4% | −10.0 pts | −10.0 pts |
| 1 year | +5.7% | +6.1% | −13.4 pts | −13.0 pts |
| Since launch CPST Sep 2024 · ZSEP Sep 2024 | +14.1% | +14.1% | −26.8 pts | −26.9 pts |
Each fund's gap is to its reference's price return, dividends left out: the basis the outcome period uses. Source: ETFIQ. Open this comparison in the app →
On the same fields
As of Oct 13, 2026. Source: ETFIQ.
About CPST
The fund's price can fall 0.5% from here before the buffer starts absorbing losses, by the issuer's figure. In index terms, SPY can fall 2.1% 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. 322 days remained on Oct 13, 2026. On Aug 31, 2027 the period ends and a new cap is set.
About ZSEP
From its price on Oct 13, 2026, the fund can gain about 8.0% more before it reaches its cap. The fund's price can fall 0.8% from here before the buffer starts absorbing losses, by the issuer's figure. In index terms, SPY can fall 1.3% from today's level to the point where the buffer begins.
Questions people ask
ETFIQ links to the documents behind every figure; a link is not an endorsement. A comparison is not a recommendation.
How this is computed
ETFIQ calculates every figure from each issuer’s published outcome-period terms. Buffer ETFs hold options on an index, not shares, so there is no holdings overlap to report.
Every figure is an ETFIQ calculation with distributions reinvested.
Cite this pageCitation, APA and Markdown
ETFIQ, CPST against ZSEP, data as of Oct 13, 2026. https://etfiq.com/compare/buffer/cpst-vs-zsep
ETFIQ. (Oct 13, 2026). CPST against ZSEP. Retrieved from https://etfiq.com/compare/buffer/cpst-vs-zsep
[CPST against ZSEP (ETFIQ, Oct 13, 2026)](https://etfiq.com/compare/buffer/cpst-vs-zsep)
Free to use with attribution for figures ETFIQ computes; issuer data stays under its owner's terms.