The Department of Revenue (DOR) is administering the following 2023 TABOR refund mechanism, primarily through the Colorado Individual Income Tax Return (DR 0104):

Sales Tax Refund - Eligible 2023 full-year residents may claim this refund by filing in the manner described below by the appropriate deadline. The refund is $800 for one qualifying taxpayer or $1,600 for two qualifying taxpayers filing jointly. 

• File a 2023 DR 0104 by April 15, 2024, if you: 
  • Were at least 18 years old when the tax year began, 
  • Do not have a Colorado income tax liability,
  • Are not claiming a refund of wage withholding, and
  • Are not otherwise required to file a Colorado return because you have no federal filing requirement.
• File a 2023 DR 0104 by October 15, 2024, if you: 
  • Have a Colorado income tax liability,
  • Claim a refund of wage withholding, or
  • Are required to file a Colorado return because you are required to file a federal return.

So based on this I assume a 16 year old can get the refund, in my client's case...the second one on the second list..claim a refund of wage withholding.  So I will go with ProSeries' automatic box checking and hope it doesn't come back to bite later on.