Colorado — Amended Income Tax Return Form
More about the Colorado Form 104X Amended Return
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File Now with TurboTaxWe last updated Colorado Form 104X in February 2025 from the Colorado Department of Revenue. This form is for income earned in tax year 2024, with tax returns due in April 2025. We will update this page with a new version of the form for 2026 as soon as it is made available by the Colorado government.
Other Colorado Individual Income Tax Forms:
In addition to information about Colorado's income tax brackets, Tax-Brackets.org provides a total of 65 Colorado income tax forms, as well as many federal income tax forms. Here's a list of some of the most commonly used Colorado tax forms:
| Form Code | Form Name |
|---|---|
| Form 104PN | Part-Year/Nonresident Computation Form |
| Form DR 1778 | E-Filer Attachment Form |
| Form DR 1079 | Real Property Interest - Payment of Withholding |
| Form DR 0102 | Deceased Taxpayer - Claim for Refund |
| Form DR 158-I | Individual Income Tax Automatic Filing Extension |
View all 65 Colorado Income Tax Forms
Disclaimer: While we do our best to keep Form 104X up to date and complete on Tax-Brackets.org, we cannot be held liable for errors or omissions. Is this form missing or out-of-date? Please let us know so we can fix it!
Tax Form Sources:
- Colorado Department of Revenue ( http://www.colorado.gov/cs/Satellite/Revenue/REVX/1176842266433 )
- Department of Revenue Income Tax Forms ( https://www.colorado.gov/pacific/tax/forms-number-order )