Electrical Permit in Thornton, Colorado

Thornton requires an electrical permit for: Electrical contractor must hold a current State of Colorado Electrical Contractor license (issued by DORA's State Electrical Board) AND a City of Thornton Electrical contractor license (Class D Specialty — no City fee, but state and master licenses are a prerequisite); City of Thornton Electrical Contractor Registration is valid for two (2) years (longer than the standard one-year cycle for other Thornton contractor license classes); Main service panel upgrades, rewiring, new circuits, and EV charger installations require a permit; Homeowners doing electrical work on their own private residence are exempt from the City contractor-license requirement (per Thornton City Code Sec. 10-121), but the permit itself is still required; Governed by the National Electrical Code edition currently adopted by the State of Colorado (2023 NEC as of this code cycle); Thornton's adoption occurs automatically and simultaneously with the State's adoption (City Code Sec. 10-162), so Thornton does not independently amend the NEC edition/timing; Applications submitted via the CityView Portal. If your project isn't listed, confirm with City of Thornton — City Development, Building Inspection Division at 303-538-7250 before starting work.

In Thornton, the published Electrical Permit Fee — trade valuation $0 to $1,000 is: $30.00. Additional published fees: Electrical Permit Fee — trade valuation $1,001 and up — $30.00 for the first $1,000 plus $10.00 for each additional $1,000 or fraction thereof; Mechanical, Electrical & Plumbing Fee — New Single Family Dwelling (combined) — $100.00; Electric Meter (Miscellaneous Fee) — $25.00; Contractor License — Class D Specialty (Electrical) — No fee. These are the jurisdiction's own published figures — see the fee schedule table and source citations on this page.

Plan review for an electrical permit in Thornton typically runs 0–13 business days. This is an estimate, not a published figure — confirm current review times with City of Thornton — City Development, Building Inspection Division at 303-538-7250.

You'll need: Electrical Permit Application (CityView Portal). Depending on your project, Thornton may also ask for: Sub-Contractor Permission Form. See the required-documents checklist on this page for details on each.

Thornton requires 2 inspection(s) for an electrical permit, in order: Rough-In, Final. Schedule each through City of Thornton — City Development, Building Inspection Division (303-538-7250).

Apply through City of Thornton — City Development, Building Inspection Division at 9500 Civic Center Drive, Thornton, CO 80229. Phone: 303-538-7250, email: buildings@thorntonco.gov. Office hours: Mon–Fri, 8:00 a.m.–5:00 p.m. (counter payments 8:00 a.m.–4:30 p.m.). Official information: https://www.thorntonco.gov/business-development/city-development/building-permits-inspections.

The City of Thornton's Building Inspection Division (buildings@thorntonco.gov, 303-538-7250) issues and inspects electrical permits for all work within Thornton city limits. Electrical contractors must separately hold a current State of Colorado Electrical Contractor license and Master Electrician license (issued by DORA's State Electrical Board) as a prerequisite to obtaining Thornton's own Electrical Class D Specialty contractor license, which carries no additional City fee.

Thornton automatically adopts whatever National Electrical Code (NEC) edition the State of Colorado has currently adopted, per Thornton City Code Sec. 10-162 — currently the 2023 NEC. The City's adoption occurs simultaneously with the State's, so there is no separate Thornton-specific NEC edition or effective date to track.