Development Fees

“The City of Thornton, has issued a safety warning regarding fraudulent emails and phone calls, advising that the city will never ask for payments via gift cards, peer-to-peer cash apps, cryptocurrency, or unsolicited wire transfers

To ensure safety when making payments to the City of Thornton as of March 2026, please remember these following points:

• Official Communication: Emails will only come from an @thorntonco.gov address.
• Secure Payments: Valid payment links will always contain ThorntonCO.gov in the URL.
• Verification: If you are unsure about a request or invoice, call 303-538-7295 to verify its validity.
• Safety Warning: The city will never ask for passwords, credit card numbers, or gift cards via email or phone.
• Wire Transfers: These are only accepted if requested by the payee directly through the city's finance department.”

​For building permit and inspection fees, please contact the Building Inspection division:
Building Inspections | 303-538-7250 | buildings@thorntonco.gov 

For landscaping permit and fees, please read the Landscaping Permit Application form.

Water and Sewer Connection Fee Schedule Effective 1/1/2026

Connection Fees - Quick Reference Guide

The following list of fees includes most fees that are associated with land development in the City of Thornton. The list is not a comprehensive list of all fees.

Fees include one initial and two subsequent staff reviews of the application and supporting documentation. Subject to the Director’s discretion, each additional review by staff shall be assessed additional review fees equal to twenty-five percent (25%) of the original application fee.

Planning & Zoning Fees