There are two addresses to mail your CO Form 104 depending on if you are including a payment or not -
If you are filing this return with a check or
payment, please mail the return to:
COLORADO DEPARTMENT OF REVENUE
Denver, CO 80261-0006
If you are filing this return without a check or
payment, please mail the return to:
COLORADO DEPARTMENT OF REVENUE
Denver, CO 80261-0005
