# EDGAR Filing Document

**Accession Number:** 0001579881
**File Stem:** 0001104659-26-005801
**Filing Date:** 2026-1
**Character Count:** 22616
**Document Hash:** 913b67ecdf884eb0ccc4c0936b5b3e42
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-26-005801.hdr.sgml**: 20260122

**ACCESSION NUMBER**: 0001104659-26-005801

**CONFORMED SUBMISSION TYPE**: 497

**PUBLIC DOCUMENT COUNT**: 80

**FILED AS OF DATE**: 20260122

**DATE AS OF CHANGE**: 20260122

**EFFECTIVENESS DATE**: 20260122

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Calamos ETF Trust
- **CENTRAL INDEX KEY:** 0001579881

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DE

**FILING VALUES:**
- **FORM TYPE:** 497
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-191151
- **FILM NUMBER:** 26551967

**BUSINESS ADDRESS:**
- **STREET 1:** 2020 CALAMOS COURT
- **CITY:** NAPERVILLE
- **STATE:** IL
- **ZIP:** 60563
- **BUSINESS PHONE:** 630-245-8394

**MAIL ADDRESS:**
- **STREET 1:** 2020 CALAMOS COURT
- **CITY:** NAPERVILLE
- **STATE:** IL
- **ZIP:** 60563

## Series and Classes Contracts Data

### Calamos Nasdaq-100 Structured Alt Protection ETF - December (Series ID: S000084790)

---

|  |  |  |
|:---|:---|:---|
| Class Name                                                  | Ticker Symbol | Class ID   |
| Calamos Nasdaq-100 Structured Alt Protection ETF - December | CPNQ          | C000249271 |

---

### Calamos Nasdaq-100 Structured Alt Protection ETF - June (Series ID: S000084791)

---

|  |  |  |
|:---|:---|:---|
| Class Name                                              | Ticker Symbol | Class ID   |
| Calamos Nasdaq-100 Structured Alt Protection ETF - June | CPNJ          | C000249272 |

---

### Calamos Nasdaq-100 Structured Alt Protection ETF - March (Series ID: S000084792)

---

|  |  |  |
|:---|:---|:---|
| Class Name                                               | Ticker Symbol | Class ID   |
| Calamos Nasdaq-100 Structured Alt Protection ETF - March | CPNM          | C000249273 |

---

### Calamos Nasdaq-100 Structured Alt Protection ETF - September (Series ID: S000084793)

---

|  |  |  |
|:---|:---|:---|
| Class Name                                                   | Ticker Symbol | Class ID   |
| Calamos Nasdaq-100 Structured Alt Protection ETF - September | CPNS          | C000249274 |

---

### Calamos S&P 500 Structured Alt Protection ETF - August (Series ID: S000084798)

---

|  |  |  |
|:---|:---|:---|
| Class Name                                             | Ticker Symbol | Class ID   |
| Calamos S&P 500 Structured Alt Protection ETF - August | CPSA          | C000249279 |

---

### Calamos S&P 500 Structured Alt Protection ETF - September (Series ID: S000084799)

---

|  |  |  |
|:---|:---|:---|
| Class Name                                                | Ticker Symbol | Class ID   |
| Calamos S&P 500 Structured Alt Protection ETF - September | CPST          | C000249280 |

---

### Calamos S&P 500 Structured Alt Protection ETF - May (Series ID: S000084800)

---

|  |  |  |
|:---|:---|:---|
| Class Name                                          | Ticker Symbol | Class ID   |
| Calamos S&P 500 Structured Alt Protection ETF - May | CPSM          | C000249281 |

---

### Calamos S&P 500 Structured Alt Protection ETF - July (Series ID: S000084801)

---

|  |  |  |
|:---|:---|:---|
| Class Name                                           | Ticker Symbol | Class ID   |
| Calamos S&P 500 Structured Alt Protection ETF - July | CPSJ          | C000249282 |

---

### Calamos Russell 2000 Structured Alt Protection ETF - April (Series ID: S000085629)

---

|  |  |
|:---|:---|
| Class Name                                                 | Class ID   |
| Calamos Russell 2000 Structured Alt Protection ETF - April | C000250958 |

---

### Calamos Russell 2000 Structured Alt Protection ETF - January (Series ID: S000085630)

---

|  |  |
|:---|:---|
| Class Name                                                   | Class ID   |
| Calamos Russell 2000 Structured Alt Protection ETF - January | C000250959 |

---

### Calamos Russell 2000 Structured Alt Protection ETF - July (Series ID: S000085631)

---

|  |  |
|:---|:---|
| Class Name                                                | Class ID   |
| Calamos Russell 2000 Structured Alt Protection ETF - July | C000250960 |

---

### Calamos Russell 2000 Structured Alt Protection ETF - October (Series ID: S000085632)

---

|  |  |
|:---|:---|
| Class Name                                                   | Class ID   |
| Calamos Russell 2000 Structured Alt Protection ETF - October | C000250961 |

---

### Calamos S&P 500 Structured Alt Protection ETF - April (Series ID: S000086979)

---

|  |  |
|:---|:---|
| Class Name                                            | Class ID   |
| Calamos S&P 500 Structured Alt Protection ETF - April | C000252649 |

---

### Calamos S&P 500 Structured Alt Protection ETF - December (Series ID: S000086980)

---

|  |  |
|:---|:---|
| Class Name                                               | Class ID   |
| Calamos S&P 500 Structured Alt Protection ETF - December | C000252650 |

---

### Calamos S&P 500 Structured Alt Protection ETF - February (Series ID: S000086981)

---

|  |  |
|:---|:---|
| Class Name                                               | Class ID   |
| Calamos S&P 500 Structured Alt Protection ETF - February | C000252651 |

---

### Calamos S&P 500 Structured Alt Protection ETF - January (Series ID: S000086982)

---

|  |  |
|:---|:---|
| Class Name                                              | Class ID   |
| Calamos S&P 500 Structured Alt Protection ETF - January | C000252652 |

---

### Calamos S&P 500 Structured Alt Protection ETF - June (Series ID: S000086983)

---

|  |  |
|:---|:---|
| Class Name                                           | Class ID   |
| Calamos S&P 500 Structured Alt Protection ETF - June | C000252653 |

---

### Calamos S&P 500 Structured Alt Protection ETF - March (Series ID: S000086984)

---

|  |  |
|:---|:---|
| Class Name                                            | Class ID   |
| Calamos S&P 500 Structured Alt Protection ETF - March | C000252654 |

---

### Calamos S&P 500 Structured Alt Protection ETF - November (Series ID: S000086985)

---

|  |  |
|:---|:---|
| Class Name                                               | Class ID   |
| Calamos S&P 500 Structured Alt Protection ETF - November | C000252655 |

---

### Calamos S&P 500 Structured Alt Protection ETF - October (Series ID: S000086986)

---

|  |  |
|:---|:---|
| Class Name                                              | Class ID   |
| Calamos S&P 500 Structured Alt Protection ETF - October | C000252656 |

---

### Calamos Bitcoin 80 Series Structured Alt Protection ETF - January (Series ID: S000090058)

---

|  |  |
|:---|:---|
| Class Name                                                        | Class ID   |
| Calamos Bitcoin 80 Series Structured Alt Protection ETF - January | C000256935 |

---

### Calamos Bitcoin 80 Series Structured Alt Protection ETF - April (Series ID: S000090059)

---

|  |  |
|:---|:---|
| Class Name                                                      | Class ID   |
| Calamos Bitcoin 80 Series Structured Alt Protection ETF - April | C000256936 |

---

### Calamos Bitcoin 80 Series Structured Alt Protection ETF - July (Series ID: S000090060)

---

|  |  |
|:---|:---|
| Class Name                                                     | Class ID   |
| Calamos Bitcoin 80 Series Structured Alt Protection ETF - July | C000256937 |

---

### Calamos Bitcoin 80 Series Structured Alt Protection ETF - October (Series ID: S000090061)

---

|  |  |
|:---|:---|
| Class Name                                                        | Class ID   |
| Calamos Bitcoin 80 Series Structured Alt Protection ETF - October | C000256938 |

---

### Calamos Bitcoin 90 Series Structured Alt Protection ETF - January (Series ID: S000090064)

---

|  |  |
|:---|:---|
| Class Name                                                        | Class ID   |
| Calamos Bitcoin 90 Series Structured Alt Protection ETF - January | C000256941 |

---

### Calamos Bitcoin 90 Series Structured Alt Protection ETF - April (Series ID: S000090065)

---

|  |  |
|:---|:---|
| Class Name                                                      | Class ID   |
| Calamos Bitcoin 90 Series Structured Alt Protection ETF - April | C000256942 |

---

### Calamos Bitcoin 90 Series Structured Alt Protection ETF - July (Series ID: S000090066)

---

|  |  |
|:---|:---|
| Class Name                                                     | Class ID   |
| Calamos Bitcoin 90 Series Structured Alt Protection ETF - July | C000256943 |

---

### Calamos Bitcoin 90 Series Structured Alt Protection ETF - October (Series ID: S000090067)

---

|  |  |
|:---|:---|
| Class Name                                                        | Class ID   |
| Calamos Bitcoin 90 Series Structured Alt Protection ETF - October | C000256944 |

---

### Calamos Bitcoin Structured Alt Protection ETF - January (Series ID: S000090114)

---

|  |  |
|:---|:---|
| Class Name                                              | Class ID   |
| Calamos Bitcoin Structured Alt Protection ETF - January | C000256995 |

---

### Calamos Bitcoin Structured Alt Protection ETF - April (Series ID: S000090115)

---

|  |  |
|:---|:---|
| Class Name                                            | Class ID   |
| Calamos Bitcoin Structured Alt Protection ETF - April | C000256996 |

---

### Calamos Bitcoin Structured Alt Protection ETF - July (Series ID: S000090116)

---

|  |  |
|:---|:---|
| Class Name                                           | Class ID   |
| Calamos Bitcoin Structured Alt Protection ETF - July | C000256997 |

---

### Calamos Bitcoin Structured Alt Protection ETF - October (Series ID: S000090117)

---

|  |  |
|:---|:---|
| Class Name                                              | Class ID   |
| Calamos Bitcoin Structured Alt Protection ETF - October | C000256998 |

---

## Series and Classes Contracts Data

### Calamos Nasdaq-100 Structured Alt Protection ETF - December (Series ID: S000084790)

| Class ID   | Class Name                                                  | Ticker Symbol   |
|:---|:---|:---|
| C000249271 | Calamos Nasdaq-100 Structured Alt Protection ETF - December | CPNQ            |

### Calamos Nasdaq-100 Structured Alt Protection ETF - June (Series ID: S000084791)

| Class ID   | Class Name                                              | Ticker Symbol   |
|:---|:---|:---|
| C000249272 | Calamos Nasdaq-100 Structured Alt Protection ETF - June | CPNJ            |

### Calamos Nasdaq-100 Structured Alt Protection ETF - March (Series ID: S000084792)

| Class ID   | Class Name                                               | Ticker Symbol   |
|:---|:---|:---|
| C000249273 | Calamos Nasdaq-100 Structured Alt Protection ETF - March | CPNM            |

### Calamos Nasdaq-100 Structured Alt Protection ETF - September (Series ID: S000084793)

| Class ID   | Class Name                                                   | Ticker Symbol   |
|:---|:---|:---|
| C000249274 | Calamos Nasdaq-100 Structured Alt Protection ETF - September | CPNS            |

### Calamos S&P 500 Structured Alt Protection ETF - August (Series ID: S000084798)

| Class ID   | Class Name                                             | Ticker Symbol   |
|:---|:---|:---|
| C000249279 | Calamos S&P 500 Structured Alt Protection ETF - August | CPSA            |

### Calamos S&P 500 Structured Alt Protection ETF - September (Series ID: S000084799)

| Class ID   | Class Name                                                | Ticker Symbol   |
|:---|:---|:---|
| C000249280 | Calamos S&P 500 Structured Alt Protection ETF - September | CPST            |

### Calamos S&P 500 Structured Alt Protection ETF - May (Series ID: S000084800)

| Class ID   | Class Name                                          | Ticker Symbol   |
|:---|:---|:---|
| C000249281 | Calamos S&P 500 Structured Alt Protection ETF - May | CPSM            |

### Calamos S&P 500 Structured Alt Protection ETF - July (Series ID: S000084801)

| Class ID   | Class Name                                           | Ticker Symbol   |
|:---|:---|:---|
| C000249282 | Calamos S&P 500 Structured Alt Protection ETF - July | CPSJ            |

### Calamos Russell 2000 Structured Alt Protection ETF - April (Series ID: S000085629)

| Class ID   | Class Name                                                 | Ticker Symbol   |
|:---|:---|:---|
| C000250958 | Calamos Russell 2000 Structured Alt Protection ETF - April |  |

### Calamos Russell 2000 Structured Alt Protection ETF - January (Series ID: S000085630)

| Class ID   | Class Name                                                   | Ticker Symbol   |
|:---|:---|:---|
| C000250959 | Calamos Russell 2000 Structured Alt Protection ETF - January |  |

### Calamos Russell 2000 Structured Alt Protection ETF - July (Series ID: S000085631)

| Class ID   | Class Name                                                | Ticker Symbol   |
|:---|:---|:---|
| C000250960 | Calamos Russell 2000 Structured Alt Protection ETF - July |  |

### Calamos Russell 2000 Structured Alt Protection ETF - October (Series ID: S000085632)

| Class ID   | Class Name                                                   | Ticker Symbol   |
|:---|:---|:---|
| C000250961 | Calamos Russell 2000 Structured Alt Protection ETF - October |  |

### Calamos S&P 500 Structured Alt Protection ETF - April (Series ID: S000086979)

| Class ID   | Class Name                                            | Ticker Symbol   |
|:---|:---|:---|
| C000252649 | Calamos S&P 500 Structured Alt Protection ETF - April |  |

### Calamos S&P 500 Structured Alt Protection ETF - December (Series ID: S000086980)

| Class ID   | Class Name                                               | Ticker Symbol   |
|:---|:---|:---|
| C000252650 | Calamos S&P 500 Structured Alt Protection ETF - December |  |

### Calamos S&P 500 Structured Alt Protection ETF - February (Series ID: S000086981)

| Class ID   | Class Name                                               | Ticker Symbol   |
|:---|:---|:---|
| C000252651 | Calamos S&P 500 Structured Alt Protection ETF - February |  |

### Calamos S&P 500 Structured Alt Protection ETF - January (Series ID: S000086982)

| Class ID   | Class Name                                              | Ticker Symbol   |
|:---|:---|:---|
| C000252652 | Calamos S&P 500 Structured Alt Protection ETF - January |  |

### Calamos S&P 500 Structured Alt Protection ETF - June (Series ID: S000086983)

| Class ID   | Class Name                                           | Ticker Symbol   |
|:---|:---|:---|
| C000252653 | Calamos S&P 500 Structured Alt Protection ETF - June |  |

### Calamos S&P 500 Structured Alt Protection ETF - March (Series ID: S000086984)

| Class ID   | Class Name                                            | Ticker Symbol   |
|:---|:---|:---|
| C000252654 | Calamos S&P 500 Structured Alt Protection ETF - March |  |

### Calamos S&P 500 Structured Alt Protection ETF - November (Series ID: S000086985)

| Class ID   | Class Name                                               | Ticker Symbol   |
|:---|:---|:---|
| C000252655 | Calamos S&P 500 Structured Alt Protection ETF - November |  |

### Calamos S&P 500 Structured Alt Protection ETF - October (Series ID: S000086986)

| Class ID   | Class Name                                              | Ticker Symbol   |
|:---|:---|:---|
| C000252656 | Calamos S&P 500 Structured Alt Protection ETF - October |  |

### Calamos Bitcoin 80 Series Structured Alt Protection ETF - January (Series ID: S000090058)

| Class ID   | Class Name                                                        | Ticker Symbol   |
|:---|:---|:---|
| C000256935 | Calamos Bitcoin 80 Series Structured Alt Protection ETF - January |  |

### Calamos Bitcoin 80 Series Structured Alt Protection ETF - April (Series ID: S000090059)

| Class ID   | Class Name                                                      | Ticker Symbol   |
|:---|:---|:---|
| C000256936 | Calamos Bitcoin 80 Series Structured Alt Protection ETF - April |  |

### Calamos Bitcoin 80 Series Structured Alt Protection ETF - July (Series ID: S000090060)

| Class ID   | Class Name                                                     | Ticker Symbol   |
|:---|:---|:---|
| C000256937 | Calamos Bitcoin 80 Series Structured Alt Protection ETF - July |  |

### Calamos Bitcoin 80 Series Structured Alt Protection ETF - October (Series ID: S000090061)

| Class ID   | Class Name                                                        | Ticker Symbol   |
|:---|:---|:---|
| C000256938 | Calamos Bitcoin 80 Series Structured Alt Protection ETF - October |  |

### Calamos Bitcoin 90 Series Structured Alt Protection ETF - January (Series ID: S000090064)

| Class ID   | Class Name                                                        | Ticker Symbol   |
|:---|:---|:---|
| C000256941 | Calamos Bitcoin 90 Series Structured Alt Protection ETF - January |  |

### Calamos Bitcoin 90 Series Structured Alt Protection ETF - April (Series ID: S000090065)

| Class ID   | Class Name                                                      | Ticker Symbol   |
|:---|:---|:---|
| C000256942 | Calamos Bitcoin 90 Series Structured Alt Protection ETF - April |  |

### Calamos Bitcoin 90 Series Structured Alt Protection ETF - July (Series ID: S000090066)

| Class ID   | Class Name                                                     | Ticker Symbol   |
|:---|:---|:---|
| C000256943 | Calamos Bitcoin 90 Series Structured Alt Protection ETF - July |  |

### Calamos Bitcoin 90 Series Structured Alt Protection ETF - October (Series ID: S000090067)

| Class ID   | Class Name                                                        | Ticker Symbol   |
|:---|:---|:---|
| C000256944 | Calamos Bitcoin 90 Series Structured Alt Protection ETF - October |  |

### Calamos Bitcoin Structured Alt Protection ETF - January (Series ID: S000090114)

| Class ID   | Class Name                                              | Ticker Symbol   |
|:---|:---|:---|
| C000256995 | Calamos Bitcoin Structured Alt Protection ETF - January |  |

### Calamos Bitcoin Structured Alt Protection ETF - April (Series ID: S000090115)

| Class ID   | Class Name                                            | Ticker Symbol   |
|:---|:---|:---|
| C000256996 | Calamos Bitcoin Structured Alt Protection ETF - April |  |

### Calamos Bitcoin Structured Alt Protection ETF - July (Series ID: S000090116)

| Class ID   | Class Name                                           | Ticker Symbol   |
|:---|:---|:---|
| C000256997 | Calamos Bitcoin Structured Alt Protection ETF - July |  |

### Calamos Bitcoin Structured Alt Protection ETF - October (Series ID: S000090117)

| Class ID   | Class Name                                              | Ticker Symbol   |
|:---|:---|:---|
| C000256998 | Calamos Bitcoin Structured Alt Protection ETF - October |  |

?xml version='1.0' encoding='ASCII'?

**CALAMOS ETF TRUST**

(the "Trust")

Supplement dated January 22, 2026 to the CALAMOS<sup>®</sup> FAMILY OF FUNDS (the "Funds")

Prospectuses dated November 28, 2025, as amended, with respect to:

Calamos S&P 500® Structured Alt Protection ETF® – January, Calamos S&P 500® Structured Alt Protection ETF® – February, Calamos S&P 500® Structured Alt Protection ETF® – March, Calamos S&P 500® Structured Alt Protection ETF® – April, Calamos S&P 500® Structured Alt Protection ETF® – May, Calamos S&P 500® Structured Alt Protection ETF® – June, Calamos S&P 500® Structured Alt Protection ETF® – July, Calamos S&P 500® Structured Alt Protection ETF® – August, Calamos S&P 500® Structured Alt Protection ETF® – September, Calamos S&P 500® Structured Alt Protection ETF® – October, Calamos S&P 500® Structured Alt Protection ETF® – November, Calamos S&P 500® Structured Alt Protection ETF® – December

Calamos Nasdaq-100® Structured Alt Protection ETF® – March, Calamos Nasdaq-100® Structured Alt Protection ETF® – June, Calamos Nasdaq-100® Structured Alt Protection ETF® – September, Calamos Nasdaq-100® Structured Alt Protection ETF® – December

Calamos Russell 2000® Structured Alt Protection ETF® – January, Calamos Russell 2000® Structured Alt Protection ETF® – April, Calamos Russell 2000® Structured Alt Protection ETF® – July, Calamos Russell 2000® Structured Alt Protection ETF® – October

Calamos Bitcoin Structured Alt Protection ETF® – January, Calamos Bitcoin Structured Alt Protection ETF® – April, Calamos Bitcoin Structured Alt Protection ETF® – July, Calamos Bitcoin Structured Alt Protection ETF® – October, Calamos Bitcoin 90 Series Structured Alt Protection ETF® – January, Calamos Bitcoin 90 Series Structured Alt Protection ETF® – April, Calamos Bitcoin 90 Series Structured Alt Protection ETF® – July, Calamos Bitcoin 90 Series Structured Alt Protection ETF® – October, Calamos Bitcoin 80 Series Structured Alt Protection ETF® – January, Calamos Bitcoin 80 Series Structured Alt Protection ETF® – April, Calamos Bitcoin 80 Series Structured Alt Protection ETF® – July, Calamos Bitcoin 80 Series Structured Alt Protection ETF® – October

*This supplement updates certain information contained in each of the Prospectuses noted above and should be attached to the Prospectuses and retained for future reference.*

*Capitalized terms and certain other terms used in this supplement, unless otherwise defined in this supplement, have the meanings assigned to them in the Prospectuses.*

Effective immediately, the following changes are made to the Prospectuses:

Each Fund's prospectus contains one or more instances of a section titled "Subsequent Outcome Periods". Each such section is hereby deleted in its entirety and replaced with the following:

Approximately one week prior to the end of each Outcome Period, the Fund will file a prospectus supplement that will alert existing shareholders that the Outcome Period is approaching its conclusion and disclose the anticipated Cap range for the next Outcome Period. This filing will be mailed to existing shareholders. Following the close of business on the last day of the Outcome Period, the Fund will file a prospectus supplement that discloses the Fund's Cap for the next Outcome Period. This filing will be mailed to existing shareholders. There is no guarantee the Cap will be within the anticipated Cap range. The information referenced above will also be available on the Fund's website at <u>www.calamos.com</u>.

**Please retain this supplement for future reference**