To run a serial number on a gun, you ask someone with access to the FBI’s stolen-firearms records to look it up for you, because private citizens can’t query those records directly. Your two options are a local police department or sheriff’s office, which can check the National Crime Information Center (NCIC) Gun File, or, as of August 2025, a licensed firearms dealer, who can now run the same check before taking a used gun in. Either route tells you the one thing that matters most before you buy: whether the firearm has been reported stolen.
Find the Serial Number First
You can’t check anything without the number. Federal law requires every licensed manufacturer and importer to mark each firearm with a unique serial number on the frame or receiver.1Office of the Law Revision Counsel. 18 USC 923 – Licensing Where to look depends on the gun:
- On handguns, the number is usually on the frame near the trigger guard, on the slide, or beneath the grip panel.
- On rifles and shotguns, it’s typically on the receiver or barrel. For AR-15-style rifles with split receivers, the serialized part is the lower receiver.
Write it down exactly, including any letters and leading zeros. You’ll use it for every step that follows.
Ask Local Police or the Sheriff’s Office
The most direct way to check a gun is to call your local police department or sheriff’s office and ask them to run the serial number through NCIC. Some agencies handle it over the phone or at a front desk; others may ask you to bring the firearm in. Be ready to give the full serial number and explain how the gun came into your hands or why you’re thinking about buying it. There’s no standardized fee, and many departments do it at no charge, though policies vary.
NCIC’s Gun File contains records of stolen, recovered, lost, and felony-linked weapons, with the serial number, caliber, make, type, and model for each.2Federal Bureau of Investigation. Privacy Impact Assessment FBI/NCIC Only criminal justice agencies can enter records, and query access is generally limited to authorized law enforcement.3Federal Bureau of Investigation. National Crime Information Center (NCIC) That’s why the request has to go through them.
If the gun comes back clean, you’ll usually get verbal confirmation. Ask for something in writing if you can. If it comes back stolen, law enforcement takes it. That part is not negotiable, and it’s covered below.
Ask a Licensed Firearms Dealer
As of August 4, 2025, the FBI has made stolen-gun record checks available to all federal firearms licensees.4Federal Bureau of Investigation. NCIC Gun File Correspondence 2025 The change came out of the Bipartisan Safer Communities Act of 2022, which directed the Attorney General to give dealers a way to verify whether firearms offered for sale had been reported stolen.5Congress.gov. Text – 117th Congress (2021-2022): Bipartisan Safer Communities Act Dealers can partner with a local law enforcement agency, receive a state-provided extract of the NCIC stolen-gun data, or use the FBI’s E-Check system.6Federal Bureau of Investigation. New Rule Provides Federal Firearms Licensees Access to FBI Records of Stolen Firearms
In practical terms, if you’re buying a used gun from a dealer or routing a private sale through an FFL for a background check, the dealer can now check whether the firearm is stolen before completing the transfer. Not every dealer has set up the capability yet, so call ahead. If a search flags a gun, the FFL can report it to law enforcement.6Federal Bureau of Investigation. New Rule Provides Federal Firearms Licensees Access to FBI Records of Stolen Firearms
What the Check Can and Cannot Tell You
An NCIC check tells you one thing with high confidence: whether the firearm has been reported stolen, recovered, lost, or used in a felony.2Federal Bureau of Investigation. Privacy Impact Assessment FBI/NCIC A clean result means the gun doesn’t appear in any of those categories. It does not mean the gun has never been stolen. It means no one has reported it.
What the check will not give you is an ownership history. Federal law prohibits any national system of registration of firearms, firearms owners, or firearms transactions.7Office of the Law Revision Counsel. 18 USC 926 – Rules and Regulations The ATF’s National Tracing Center can follow a firearm from the manufacturer or importer through wholesalers and retailers to the first retail purchaser, but that service is for law enforcement investigations, not private buyers, and the trail generally ends at that first sale.8Bureau of Alcohol, Tobacco, Firearms and Explosives. National Tracing Center
For model verification and production year, go straight to the manufacturer. Several, including Colt, offer online serial-number lookups that return the model and date of manufacture.9Colt’s Manufacturing Company LLC. Serial Number Lookup
A note on third-party sites. Some crowd-sourced websites and state agencies offer limited stolen-gun lookups to the public. The data can be outdated, incomplete, or contain duplicate serial numbers across different firearms. A clean result from one of these is not the same as a clean NCIC result. Use them as a preliminary screen at most, and still get an official check through law enforcement or a dealer before money changes hands.
If the Gun Is Reported Stolen
If a check comes back stolen, law enforcement will confiscate the firearm. It goes back to the rightful owner or into evidence. There is no appeal process for the person holding it, and no legal guarantee of recovering what you paid from the seller.
The buyer’s legal exposure depends on knowledge. Federal law criminalizes possession or receipt of a stolen firearm only when the person knew or had reasonable cause to believe it was stolen.10Office of the Law Revision Counsel. 18 USC 922 – Unlawful Acts A genuine good-faith purchase from someone who looked like a legitimate seller generally doesn’t meet that standard. Knowing possession or receipt carries a federal penalty of up to 10 years in prison.11Office of the Law Revision Counsel. 18 USC 924 – Penalties
The practical lesson: run the number before you hand over cash. If a seller won’t let you, walk away.
Guns With No Serial Number or a Defaced One
A serial-number check only works if there’s a number to check. If the number has been filed off, scratched out, or otherwise altered, possession is itself a federal crime under 18 U.S.C. ยง 922(k), for any firearm that has at some point been shipped or transported in interstate commerce.10Office of the Law Revision Counsel. 18 USC 922 – Unlawful Acts The penalty is up to five years in federal prison.11Office of the Law Revision Counsel. 18 USC 924 – Penalties Don’t buy it, don’t take possession, and don’t try to hold it “just to turn it in” without first calling law enforcement for instructions.
Homemade firearms are a separate situation. Federal law does not require unlicensed individuals to serialize firearms they build for their own personal use.12Federal Register. Definition of Frame or Receiver and Identification of Firearms Once such a firearm enters commercial channels, an FFL who receives it must mark it with a serial number within seven days of acquisition or before selling it, whichever comes first.13Bureau of Alcohol, Tobacco, Firearms and Explosives. Privately Made Firearms If a private seller offers you a gun with no serial number and calls it a legal homemade build, you have no way to verify who built it, whether it was stolen, or whether it was assembled from parts specifically to avoid tracing. Without a number, the seller’s word is all you have, and that isn’t enough.