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.

Online submission system coming soon — interim email process in place

Our online platform for processing firearm serial number checks is still being finalized. In the meantime, Federal Firearms Licensees can submit requests by email using the process below. Once the online system is available, we will update this page and reach out to dealers to help them get set up.

How to Submit a Request (Interim Process)

Email your request to ffljcso@co.jefferson.co.us and include the information below along with a clear photo of the serial number on the firearm. We will complete your request within three (3) business days.

Email Your Request

What to Include

Business Information

Business Name
FFL Number
Business Address
City / State / Zip
Phone Number
Email Address
Website
Contact Person

Firearm Information

Serial Number
Make
Model
Caliber / Gauge
Type of Firearm
Miscellaneous Information

Repeat these fields for each additional firearm.

Certification

Include the following certification statement, your printed name, and the date:

I certify that the information submitted is accurate and that this request is being submitted pursuant to Colorado SB 25-205.

Printed Name
Date

Questions?

Having trouble submitting your request? Call the Records Unit at (303) 271-5541.