Income Tax Due Dates & Filing Extension

Expect to get a refund this year but can't make the deadline?

If you cannot file your Colorado income tax return by the deadline of Wednesday, April 15, 2020, you may take advantage of the state’s automatic six-month extension of time to file. 

There is no form to fill out to notify the Department of Revenue that you are taking the extension, however there is no extension for tax due. The extension applies to filing Colorado income tax information, either on paper or electronically, not to any state income tax you may owe. If you expect to get a refund this year but do not make the filing deadline, you can still file your state income tax on or before October 15.

There is no extension for tax due. If you owe state income tax, 90% of the tax liability must be paid on or before Wednesday, April 15, 2020 to avoid penalties. Any remaining balance due would be subject to interest only. If you owe tax, you must either pay through Revenue Online or submit your payment with the Extension Payment Form (DR 0158-I).

What if I'm living or traveling abroad or serving in the military on the filing deadline?

If a person is out of the country on the tax filing due date in April, the deadline for filing the state return and paying any tax owed plus interest is June 15. If you need more time to file, you may file by the October 15 extension deadline but interest and penalty will apply. This extension of time to file only applies to the actual return not to funds owed.

Filing Assistance for Low-Income Taxpayers

Free Colorado income tax filing assistance is available statewide for low-income persons through