File and Pay Online
Save Time and File Online!
To file your sales and use tax return online visit the following website:
*Note: The City accepts payment by both ACH Debit and ACH Credit if you file online.
If you have any questions, please contact the Sales Tax Division at 303-538-7400.
2023 Quarterly Bag Fee Returns now available under "Forms." Please complete and mail within 20 days following each calendar quarter to:
9500 CIVIC CENTER DRIVE
THORNTON, CO 80229.
Bag Fee Form.pdf