- 1). Complete your Colorado state tax forms, which can be downloaded for free from the Colorado Department of Revenue website (see Resources). This site offers both individual and business tax forms, a "Common Questions" link and tax classes to make filing easier for businesses.
- 2). File your Colorado state taxes electronically, the method preferred by state officials. You can do this through a state-specific program called NetFile (see Resources) if you've filed Colorado taxes before, or through the IRS website via a program called FreeFile (see Resources), which offers a variety of free tax software and filing options to qualified individuals. If you don't want to or cannot file your Colorado taxes electronically, mail them to:
Colorado Department of Revenue
1375 Sherman St.
Denver, CO 80261-0005.
Use the ZIP code extension 0008 instead of 0005 if you are filing estimated taxes for the coming year. - 3). Complete your federal tax forms by using Free File software or software you purchase, by filling out printed tax forms or going through a tax specialist. You can file electronically through the IRS website or, if you're making a tax payment, mail the forms to:
Department of the Treasury
Internal Revenue Service
Fresno, CA 93888-0002
To file taxes without a payment, change the ZIP code extension to 0102.
Source...