Taxpayers and tax practitioners are encouraged to file all tax returns either through an accepted tax software product or via Revenue Online. The Department maintains a list of accepted software for C corporation income tax. The list shows supported tax software by developer name, software name and website address.
View the Accepted Software List for C Corporations to verify whether a software product is approved to process tax returns for the current tax year.
For the upcoming tax year, the list is updated as software is approved (typically by the third week of January). Some software products allow the submission of Colorado income tax estimated payments using form DR 0112EP, and extension payments using form DR 0158-C. For estimated payments, up to four payments can be scheduled at once, but the last payment must be scheduled by the January estimated payment due date. Your software provider can tell you if they support estimated payments and extension payments for Colorado.