Category Review
Full protection funds returned 5.9% as a 17% S&P 500 year tested the cap, not the floor
Calamos S&P 500 Structured Alt Protection ETF - September
$28.25+0.01 (+0.05%)
- 0.69%
- $41M
- +5.8%
- 0M sh
- $28.35
- low $26.68high $28.30
The ETF.net CPST Grade
C
Score 54 out of 100
- 8 of 39
Score 54 of 100 falls in the C band. A is 70 or higher, B 55 to under 70, C 40 to under 55, D 25 to under 40, F under 25.
Cost
The fund’s net expense ratio, ranked against its category.B62 out of 100Rank 9 of 39Mission
Whether the fund did what it promised, tested against its stated mandate.A91 out of 100Rank 1 of 3Risk
How the fund held up when markets fell: downside volatility, drawdowns and tail loss.C46 out of 100Rank 26 of 38Tradability
How easy the fund is to trade: daily volume, and how far its price strays from net asset value.C47 out of 100Rank 20 of 39Holdings
How concentrated the fund is, and how complete and current its disclosed holdings are.Durability
Whether the fund is likely to stay open, judged by its age, its assets and its issuer’s assets.B61 out of 100Rank 17 of 39
Our read on CPST
CThe September rung of Calamos's 100%-protection ladder: one year of S&P 500 price upside to a preset cap, with the full downside hedged by options before fees. Skip the drawdown, cap the rally.
The fund seeks point-to-point exposure to the positive price return of the S&P 500 through SPY, with 100% downside protection over a one-year outcome period and gains limited by a predetermined cap.
Why people hold it
- The floor is built from exchange-traded FLEX options inside a 1940 Act ETF, not a bank's IOU, and the terms reset with a fresh cap each September.sec.govcalamos.com
- At 0.69% a year, it costs exactly the median of its 100%-protection peer group. Middle of the road, no premium for the Calamos name.
- One of the stronger builds in its protection cohort, and part of a monthly ladder (CPSM, CPSA, CPSJ and siblings) all priced at 0.69%, so the start month is yours to pick.calamos.com
Worth knowing
- Protection is point-to-point, start of the outcome period to the end. Buy mid-period and your own cap and remaining cushion differ from the headline terms.calamos.com
- Upside stops at a cap set each September, and both cap and protection are quoted before the 0.69% fee comes out.calamos.com
- Exposure follows SPY's price return, so index dividends sit outside the deal and the fund isn't built to pay income.
CPST Holdings
- Stocks
- 3
- 105%
- SPDR S&P 500 ETF Trust (SPY) Long Call Option
CPST Performance
Shows how $10,000 changes over the selected period, with cash distributions reinvested at the closing price on each ex-dividend date.
Not enough history yet.Not enough history yet.Not enough history yet.
CPST$10,577
Returns run to the Oct 12, 2026 close, with cash distributions reinvested. Each period starts on the same date that many months or years earlier. Periods over one year show the average yearly return.
| Period | CPST |
|---|---|
| Year to date | +4.6% |
| 1 month | +0.7% |
| 3 months | +1.3% |
| 1 year | +5.8% |
| 3 years | — |
| 5 years | — |
| 10 years | — |
Calendar-year total return with cash distributions hypothetically reinvested at the ex-dividend date’s closing price. The current year shows year to date.
| Year | Return bar | CPST |
|---|---|---|
| 2026 YTD | +4.6% | |
| 2025 | +6.7% | |
| 2024 | +2.3% |
CPST in the news
Category Review
Index option income was not one bet this year
CPST Dividends
No distributions in the last 12 months.
CPST Risk
- 2.5%
How it’s calculated: standard deviation
The sample standard deviation of monthly total returns, multiplied by the square root of 12.
Uses up to 36 complete months, with at least 12 required. Total returns include reinvested distributions.
- 0.68
How it’s calculated: Sharpe ratio
Subtract each month’s Treasury-bill return from the fund’s monthly total return.
Divide the average of those excess returns by their sample standard deviation, then multiply by the square root of 12.
Uses up to 36 complete months, with at least 12 required. Each month uses the Treasury yield quoted at the end of the previous month.
- −3.8%
How it’s calculated: maximum drawdown
The largest percentage decline from an earlier peak, using total returns with reinvested distributions.
Uses up to five years through the last close, with at least 12 months required.
- 0.18
How it’s calculated: beta
The beta figure is supplied by FMP. The comparison index depends on the fund’s broad asset class.
CPST Cost
0.69%
CPST0.69%
- The middle half of S&P 500 Full Protection funds
- Median 0.69%
7 of the 27 S&P 500 Full Protection funds charge less.
Other funds in S&P 500 Full Protection
- BCPSNCalamos S&P 500 Structured Alt Protection ETF – NovemberExpense ratio 0.69%1 year return +6.4%
- CCPSACalamos S&P 500 Structured Alt Protection ETF – AugustExpense ratio 0.69%1 year return +6.3%
- CCPSMCalamos S&P 500 Structured Alt Protection ETF – MayExpense ratio 0.69%1 year return +5.1%
- CCPSJCalamos S&P 500 Structured Alt Protection ETF – JulyExpense ratio 0.69%1 year return +5.8%
- CCPSDCalamos ETF Trust - Calamos S&P 500 Structured Alt Protection ETF - DecemberExpense ratio 0.69%1 year return +7.0%