How to appeal a medical bill

Please do not resubmit bills as this can delay the review process. Instead, use our online appeal function for quick and easy bill appeal.

Appeal Online

To appeal online, visit and click the Sign in option in the top right corner. Then select Medical Provider.

  1. Log in with your email and password
  2. Click the Bill Search tab and select the clinic FEIN
  3. Enter the claim number, bill number or injured worker’s social security number. Then enter the date of service
  4. Click the Search button
  5. Select the bill you want to appeal
  6. Click on Appeal Bill
  7. Provide the reason for the appeal and any additional comments in the text box
  8. Provide your contact information (name, phone number, email)
  9. Click the Submit button
  10. You will receive an email confirming your appeal
  11. Forward a copy of the original EOB with supporting documentation via fax at 303.361.5820.

Start your appeal 

Appeal by Paper

If you wish to submit a paper appeal by mail:

Pinnacol Assurance

P.O. Box 469013

Denver, CO 80246

You may also fax an appeal to 303.361.5820 or email an appeal to

All appeals must include the following information:

  1. A copy of the original or corrected bill
  2. A copy of the written notice or EOB received
  3. A statement of the specific item(s) contested
  4. Clear and persuasive supporting documentation or reason for the appeal
  5. Any available additional information requested in our written notice

Rules for appealing a medical bill

The Colorado Division of Workers’ Compensation requires billing appeals be received within 60 days of Pinnacol’s EOB date. Further, appeals must include clear and persuasive supporting documentation and/or reasons for the appeal in addition to any supplementary information we may have requested from you.


Call us at 303.361.4940 or 888.852.2289 or email us at