Firearm Serial Number Checks
Colorado SB 25-205 — serial number check requests for Federal Firearms Licensees (FFLs).
About Colorado SB 25-205
Effective July 1, 2026, Colorado Senate Bill 25-205 ("Firearm Serial Number Check Request Procedure") allows a Federal Firearms Licensee (FFL) to request a firearm serial number check from local law enforcement before purchasing a firearm from a private individual. For firearms dealers located in unincorporated Jefferson County, those requests come to the Jefferson County Sheriff's Office Records Unit.
The check indicates whether a firearm has been reported stolen, lost, or is involved in an open criminal investigation. The Sheriff's Office will complete each request within three (3) business days.
How to Submit a Request
Submit your request through the Jefferson County Sheriff's Office online portal. Choose the Firearm Serial Number Check (Multiple) order type — you can include multiple firearms in a single request. We will complete your request within three (3) business days.
What You'll Need
Have the following ready before you begin your application:
- Your business information — business name, FFL number, address, phone, email, and contact person
- The serial number, make, model, caliber/gauge, and type of each firearm
- A clear photo of the serial number on each firearm
Questions?
Having trouble submitting your request? Call the Records Unit at (303) 271-6475.