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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DR 0204 - Tax Year Ending Computation of Penalty Due Based on Underpayment of Individual Estimated Income Tax

Calculation of underestimated penalty (UEP) can be difficult. We strongly recommend filing electronically or
consulting a tax professional to reduce the likelihood of errors. Review the Individual Income Tax Guide for additional information regarding the underpayment of Colorado individual estimated tax.