STATEWIDE—Taxpayers who cannot file their 2016 Colorado individual income tax return by this year’s April 18 deadline may take advantage of the state’s automatic six-month extension of time to file.

The Colorado Department of Revenue (CDOR) does not require notification if taxpayers are taking the filing extension, however there is no extension for paying the tax due. If taxpayers expect a refund this year but do not make the April filing deadline, they can still file their state income tax returns by Monday, October 16.

Taxpayers who owe state income tax must pay at least 90 percent of the tax liability by Tuesday, April 18, to avoid penalties. Any remaining balance due would be subject to interest only, as long as the return and balance owed are sent to CDOR by the October 16 extension deadline. Those who pay less than the required 90 percent of the amount due by the April deadline will be charged interest and penalty on the unpaid balance.

Taxpayers can use Revenue Online, CDOR’s free, one-stop website for filing taxes, managing accounts and checking refund status at Colorado.gov/RevenueOnline, to calculate the total tax owed, plus interest and penalty. Alternatively, they may choose to manually calculate penalty and interest using the instructions in the 2016 Colorado Individual Income Tax Form 104 booklet for lines 32 and 33, respectively.
There are two payment options for taxpayers – online with credit card or echeck on Revenue Online, or mail a payment with the form DR 0158-I: Extension Payment Voucher for Colorado Individual Income Tax.

The mailing address for this form is:

Colorado Department of Revenue
Denver, CO 80261-0008

This address and zip code are exclusive to the Colorado Department of Revenue, so a street address is not required. To ensure a mailed payment is credited to the correct account, taxpayers should include their Social Security number(s) and “2016 DR 0158-I” on the check or money order.

2016 income tax return deadlines

• April 18: Federal and State income tax returns are due. 90 percent of Colorado tax liability due.
• October 16: Automatic extension deadline for Colorado income tax returns if not filed by the April deadline. Total Colorado income taxes for 2016, including applicable penalty and interest, payments are due.