A Colorado income tax account is created for the taxpayer the first time an income tax return is filed with the Department of Revenue. The Department establishes an eight-digit Colorado Account Number (CAN) which should be used on all future income tax filings. If a corporation also has an eight-digit CAN for a sales tax license/account or a wage withholding account, that is the same number that should be used on the income tax return.
Access your tax account information through Revenue Online. Taxpayers may access their account through the Department's free service, Revenue Online. If you need help locating your account number, click here for more information.