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Avalara Help Center

Manage Colorado Notices

This article applies to:Returns Central

Get the info you need to manage notices for Colorado, including submitting a power of attorney and understanding common issues.

Power of Attorney

Colorado requires a Power of Attorney (POA) for Avalara to resolve notices for you.

To submit a POA:

  1. Obtain and complete a Colorado DR 0145 Power of Attorney form
  2. Send the completed POA form to the Colorado Department of Revenue, Denver, CO 80261-0009
  3. Send the completed POA form and notice to us by submitting a case. Processing takes about 6 - 8 weeks.

After we have a POA on file, you don't have to submit another one unless something has changed.

This POA doesn't cover notices from local jurisdictions. If you receive a notice from a local jurisdiction, contact that jurisdiction to get a POA, if one is required.

Common Issues

These are the most common notice issues to resolve for Colorado. See Manage Tax Notices for additional details about resolving notice issues.

Issue Action
Tax type mismatch

Out-of-state vendors should file the Retailers Use CO-0173 form. In-state vendors should file the Sales Tax CO-100 form.

Return type

Businesses with more than one location in the state of Colorado should file the CO-100 Outlets return. A common issue is to file the CO-100 form instead of the CO-100 Outlets form after registering another location with the state. This means locations are missed. Every location needs to be included, otherwise Colorado will reject the entire return and charge late penalties. Make sure you add all of your Colorado locations and schedule the correct return in AvaTax.

Paper filing

Paper filings are susceptible to manual errors. Also, Colorado sometimes claims that they haven't received paper returns and checks that were sent to them on time. It's best to file the returns electronically. Set up an online account with the state, then make sure your returns are scheduled to be filed electronically.


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