Which addresses this covers
The City of Thornton permits work inside its city limits, including the part of Thornton in Weld County. Northglenn, Westminster, Federal Heights and unincorporated Adams County issue their own permits.
| Tool | Search by | What it shows |
|---|---|---|
| CityView Permit Application Search | Application number, address, parcel number, contact name or address, map area | Each permit and its status |
| Monthly Building Permit Reports (PDF) | Month | Permit number, type, valuation, issued and finaled dates, address and contractor |
| Building Permits (2017-present) (City GIS) | Any field | Type, work class, status, valuation, issue date, parcel; our source |
How to look up the permits on a Thornton address
- Open the Permit Application Search.
- Start typing the street address (or the parcel number, or the permit number from your paperwork) and select it when it appears in the list.
- Open each permit on the property. Plumbing, mechanical and electrical work are separate permits from the building permit.
- Read the status (table below). The portal notes that a permit has not been issued "until the permit status reads 'Permit(s) Issued'".
- For questions about a permit, call Building Inspections at 303-538-7250 or email buildings@thorntonco.gov.
What the statuses mean
| Status in the City file | What it means | How we count it |
|---|---|---|
| Closed, Finalled, File Closed | Final inspection passed, file closed | Finished |
| Permit(s) Issued, Reactivated, Stop Work, Warranty | Active, or not closed | Open |
| Expired, Expired Closed | Lapsed before a final | Expired |
| Void, Withdrawn, Denied | Never went ahead | Left out |
Of the permits issued October 2024 to September 2025, 84.5% had finished, 12.6% had expired and 2.8% were still open by our 20 October 2026 snapshot. The City's file has a status but no final date, so we can say whether a permit finished, not how long it took.
When the record is not online
The City Clerk takes records requests through its Request for Public Records form. The page says "There are fees associated with requests for copies or requests that require significant resources" and gives Records at 303-538-7230 and Clerk@ThorntonCO.gov for questions (read 24 October 2026). Requests fall under the Colorado Open Records Act.
What our Thornton pages add
Our Thornton page adds the City's published permits up, October 2024 to September 2026:
| Kind of work | Permits (Oct 2024–Sep 2026) | Last 12 months (Oct 2025–Sep 2026) | 12 months before |
|---|---|---|---|
| Plumbing | 1,867 | 960 | 907 |
| HVAC | 1,726 | 949 | 777 |
| Remodels and repairs | 1,261 | 765 | 496 |
| Electrical | 840 | 483 | 357 |
| New homes | 738 | 327 | 411 |
| Garages, sheds and shade structures | 285 | 146 | 139 |
Remodel and repair permits rose 54% from the first year of the window to the second, while new-home permits fell 20%. 85% of the 7,766 permits were on homes, and ZIP code 80602 had the most, 2,589, in the same window. The permit statistics page has year and month counts, permits by ZIP code splits them by area, and browse permits lists the rows. To check a contractor, see How to check a contractor's license in Colorado.
What this does not tell you
Re-roof, fence and backflow permits are not counted: the City's published file stops carrying them after July 2025, so roofing is not covered here at all. Search the CityView portal for those. The file names no contractor, so there are no firm lists, and its value is the valuation declared on the application, not the final cost.
How we know this
Search fields and the issued-status note are quoted from the Thornton CityView Portal, the contact details from the City's Permits and Contractor Applications page, and the records process from the City Clerk's Request for Public Records page, all read 24 October 2026. Our counts are the City of Thornton's Building Permits (2017-present) map layer, read 20 October 2026: permits issued October 2024 to September 2026, without re-roof, fence and backflow permits.
Numbers come from public permit records in 57 cities, data through October 20, 2026. Nobody paid to be on this page and nobody can.
Questions
- How do I find out if a permit was pulled on my house in Thornton?
Open the Permit Application Search in Thornton's CityView Portal and start typing your address, parcel number or the permit number, then pick it from the list. You can also draw a box on the map to search an area. We opened the search without logging in.
- When is a Thornton permit actually issued?
The City's portal says a permit has not been issued until its status reads Permit(s) Issued. A permit is finished when it reads Closed, Finalled or File Closed.
- Can I look up Thornton permits by contractor?
The portal's search accepts the name or address of a contact on the permit, and the City's monthly Building Permit Reports list the contractor on each permit. The City's open permit file has no contractor column, so we do not rank firms.
- How do I request old Thornton permit records?
Use the City Clerk's Request for Public Records form, or call Records at 303-538-7230 or email Clerk@ThorntonCO.gov. The City says there are fees for copies and for requests that need significant resources.
- Does Thornton permit Northglenn or Westminster addresses?
No. Northglenn, Westminster, Federal Heights and unincorporated Adams County issue their own permits. Thornton does permit the part of the city that lies in Weld County.
Build your own list
Pick your city and the kind of work. Every firm with a permit on record, sorted by what you value.
Related guides
- Adams County, CO building permit search: the e-Permit Center, statuses and CORA
- Alachua County building permit search: Citizenserve, statuses and old records
- Anaheim building permit search: Anaheim NEXT and the Building Permit Report
- Arlington, VA building permit search: Permit Arlington lookups and FOIA requests
- Permit Application Search — Thornton CityView Portal (2026-10-24)
- Thornton CityView Portal (2026-10-24)
- Permits and Contractor Applications — City of Thornton (2026-10-24)
- Building Permit Report, February 2026 — City of Thornton (2026-10-24)
- Request For Public Records — City of Thornton City Clerk (2026-10-24)
- Building Permits (2017-present) — City of Thornton Permits map service (2026-10-20)