An extension to file is not an extension to pay tax.
Colorado grants an automatic 6-month extension to file, with no application required to get the extension itself. DR 0158-I (individual) and DR 0158-C (corporate) are payment vouchers, not extension requests - they are used only when a payment accompanies the extension. The tradeoff for the automatic extension is a 90% payment test.
None to obtain the extension itself; DR 0158-I / DR 0158-C used only to remit a payment with the extension
Extension length
6 months, to October 15, 2026 for calendar-year individual filers
Payment threshold
At least 90% of the net tax liability must be paid by the original April 15 due date to avoid penalty; interest still accrues on any unpaid balance
Authority
C.R.S. §39-22-608(2) (Department's rulemaking authority to grant extensions under prescribed rules)
The 90% payment threshold and the automatic, no-form-required mechanics are published as current Department of Revenue administrative guidance implementing the Department's rulemaking authority under §39-22-608(2) - confirm the current-year figure on the Department's site, since the statute itself sets the framework rather than a fixed percentage.
This page covers Colorado state income tax only. Denver separately imposes its own Occupational Privilege Tax (a flat per-employee monthly/quarterly/annual remittance, not an income tax return) with no extension mechanism of its own - see the Denver OPT page. Aurora, Greenwood Village, Sheridan, and Glendale impose the same style of local OPT, also with no extension mechanism found in any - see other Colorado OPT cities.
This page is for informational purposes only and is not legal, tax, or accounting advice. No professional relationship is created by using this site. Tax law and guidance change; verify against current primary authority before acting. Full disclaimer.