Visit "Where can I get vaccinated" or call 1-877-COVAXCO (1-877-268-2926) for vaccine information.


Contact Us By Phone & Fax



    Call the Taxpayer Helpline

    (303) 238-7378

    Taxpayer Service Representatives are available (except on state holidays)
    Monday through Friday, 8:00 a.m. to 4:30 p.m. MT

    Dedicated Phone Support


      Tax Unit Contact Phone Numbers

      Send Us a Fax

      Did you know you can fax certain forms to the Department? 

      Registration Control: 303-866-4176


      Hearing or Speech Impaired Relay Services

      To use this service, dial the appropriate number below. Give the Relay Colorado agent the number that you would like to call. The Relay Colorado agent will stay on the line to relay the information/conversation to you.

      • TTY Telephone Users: 1-800-659-2656
      • Voice Telephone Users: 1-800-659-3656