Emancipation Day - Income Tax Due Date

The filing due date for Colorado income tax returns due in 2017 is Tuesday, April 18, 2017 rather than April 15. In some years, the District of Columbia’s observance of Emancipation Day can affect the nation’s filing deadline. Because Emancipation Day falls on Sunday, April 16, it will be observed on Monday, April 17. This will push the tax filing deadline to the next business day for federal and Colorado income tax making the due date Tuesday, April 18, 2017.

Returns filed on Tuesday, April 18 will be considered as timely filed. Revenue Online will accept returns as timely filed until midnight. Returns that are mailed must be postmarked by April 18. An automatic extension to file is granted until Monday, October 16, 2017 but there is no extension to pay. See page 17 of the 104 Booklet for more information on extensions.