Deadline extended! The state-collected sales tax filing and payment deadline for January 2026 has been extended to March 2, 2026.

 
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Income Tax Forms Archive

The forms listed below are only valid for tax years 2017 and prior. When filing for a prior year, be sure to only use the versions of forms that apply to that tax year. Additionally, prior year forms cannot be used for the current tax year.

C Corporation Income

Fiduciary Income

Individual Income

If you are looking for a prior year for a tax year that is not listed above, please visit the Forms by Tax Type web page to search for a form. If you need additional forms assistance, please email DOR_TaxpayerService@state.co.us.