Before You Sign Up
Check Your Access Eligibility
Individual, fiduciary, partnership, and corporate income tax accounts are created when the first return is filed with the Colorado Department of Revenue. Then the account may be accessed and managed using Revenue Online. Step-by-step instructions on how to sign up to use Revenue Online are below.
During the Revenue Online sign up process, you will need to have one of these pieces of information to confirm your identity:
- Your most recent filed tax return
- Federal taxable income amount
- Refund amount
- Letter ID
If you have received a recent letter from the Department, you may use the Letter ID number located in the upper right corner of Department tax letters.
Request a Letter ID
If you do not have a recent letter from the Department, you may request a Letter ID number from using Revenue Online. To request a Letter ID, select “Request a Letter ID” from the "Additional Services" box on the Revenue Online homepage. A letter containing your "Letter ID" number will be sent by postal mail to the address on record with the Department. Please note that it could take up to 10 business days to receive this letter.
The Letter ID number begins with "L" and an example is below. Please note that the Letter ID is underlined here but will not be on your letter.