Jump to navigation
Save time and file online! You may use the Department's free e-file service Revenue Online to file your state income tax. You do not need a Login ID to File a Return. After you file, you have the option of setting up a Login ID and Password to view your income tax account in Revenue Online. Or, you may opt to e-file through a paid tax professional or purchase tax software to complete and file returns.
Can't Submit a Return Online?
Tax-related identity theft occurs when someone uses personal identifiable information (PII) to file a tax return to claim a fraudulent refund. PII could include Social Security numbers. The Colorado Department of Revenue (CDOR) encourages taxpayers to file early to reduce risk of someone using information to file a fraudulent return. Taxpayers should take steps to protect their personally identifiable information due to high rates of identity theft. You may be unaware that this has happened until you attempt to file your return and discover that a return already has been filed using your SSN. You may receive a message that your return “has been rejected” or “has already been filed.” The CDOR or the IRS may send you a letter saying they have identified a suspicious return using your SSN. If the IRS contacts you or the tax preparation software you or your tax professional indicates a federal or state return has already been filed using your information, contact the Department by completed our online Report Tax Fraud form to alert us so we can flag your tax account.
Also, see the Identity Theft page for information on how to report and prevent identity theft.
Note: The Colorado Department of Revenue accounting system and the public-facing Revenue Online service have not been impacted by data security breaches. The Department has employed the “two-factor” authentication industry standard when taxpayers sign up to access their tax accounts in Revenue Online as a means to prevent the personal and tax information the Department has from getting into the wrong hands.
If you owe state income tax, 90 percent of the tax liability must be paid on or before Tuesday, April 15 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 Voucher (DR 0158-I).
For information on how to file your federal return and for links to federal/state free filing services, see the Internal Revenue Service website.