To check the serial number on a gun, look on the frame or receiver — the exact spot depends on whether you have a pistol, revolver, rifle, or shotgun — then read the unique alphanumeric string engraved or stamped there. Every firearm made or imported by a licensed company since 1968 carries one, because federal regulations designate the frame or receiver as the legal identity of the firearm.1ATF eRegulations. 27 CFR 478.92 Identification of Firearms Once you have the number, you can use it to check whether the gun has been reported stolen and to keep proof-of-ownership records.
Where the Number Sits on Your Firearm
The serial number lives on the frame or receiver because that is the legally serialized component. Barrels, stocks, grips, and slides are accessories. Bring good light. Angle it so shadows fall into the engraving, which is cut to a minimum depth of .003 inches and printed no smaller than 1/16 of an inch.1ATF eRegulations. 27 CFR 478.92 Identification of Firearms If grime is in the way, wipe the area with a light solvent.
Semi-Automatic Pistols and Revolvers
On a semi-auto pistol, check the frame near the trigger guard first. Many manufacturers stamp the number on the dust cover (the flat area ahead of the trigger guard) or along the side of the frame just above it. Some pistols also carry a matching number on the slide. Revolvers usually have the number on the butt of the frame or along the bottom of the grip frame, and sometimes on the crane, which is the pivot point for the cylinder.
Rifles and Shotguns
The receiver is the primary location on both. On bolt-action rifles, look at the receiver ring or the flat portion of the receiver body. On AR-platform rifles and similar semi-autos, the number is on the lower receiver, which is the serialized part under federal law. Shotguns generally carry the number on the left or right side of the receiver, near where the barrel meets the action.
Polymer Frames and Modular Pistols
If your handgun has a polymer frame, the number is on a small metal plate permanently embedded in the frame rather than stamped into the plastic. Federal regulations specifically allow this, requiring the serial number to appear on a metal plate permanently embedded in a polymer frame or receiver.1ATF eRegulations. 27 CFR 478.92 Identification of Firearms On a Glock, for example, the plate sits on the underside of the frame ahead of the trigger guard.
Modular pistols work differently. The SIG Sauer P320 and designs like it use a removable internal chassis, called a fire control unit, that holds the serialized component. The external grip module is not serialized and can be swapped freely. If you cannot find a number on the outside of the grip, field-strip the pistol and look at the stainless steel chassis inside.
Telling the Serial Number Apart From Other Markings
A firearm carries several stamps and engravings, and only one of them is the serial number. You will also see a model number, caliber designation, patent numbers, proof marks, and the manufacturer’s name and location. Imported firearms add the country of manufacture and the name of the U.S. importer, which can crowd the area around the serial number.2eCFR. 27 CFR 478.92 Identification of Firearms and Armor Piercing Ammunition
The serial number is the marking that is unique to your specific firearm — two guns off the same production line share every other stamp. It is often the longest alphanumeric string on the frame or receiver, mixing letters and digits. When in doubt, the manufacturer’s website or owner’s manual will show you the exact location for your model.
Using the Number to Check If a Gun Is Stolen
The federal database that tracks stolen firearms is the National Crime Information Center, run by the FBI. Private citizens cannot access NCIC directly. It is restricted to authorized criminal justice agencies and, under limited circumstances, licensed firearms dealers.3eCFR. 28 CFR Part 20 – Criminal Justice Information Systems
Ask Local Law Enforcement
The most reliable route is to call your local police department or sheriff’s office and ask them to run the serial number through NCIC. Call first rather than walking in with the firearm. Explain what you need. Policies vary, and not every department treats this as a routine service, but most will accommodate the request.
One thing to know before you ask: if the gun comes back stolen, the officer will confiscate it on the spot. You will not get it back, and recovering your money from the seller is your problem. That is a strong reason to run the check before you hand over cash in a private sale, not after.
Ask a Licensed Dealer
Since 2022, the Bipartisan Safer Communities Act has authorized federally licensed dealers to run voluntary serial number checks against the NCIC stolen gun file for firearms they may take into inventory.4Federal Bureau of Investigation. NCIC Gun File Correspondence If you are selling or trading a gun through a dealer, or looking at a used gun in their case, the dealer can verify its status. Dealers can only run these checks for firearms they might actually take into inventory, not as a general public lookup.
Online Serial Number Checkers
Several websites offer to search serial numbers against stolen-gun lists. These private databases rely on voluntary self-reporting by theft victims and are nowhere near comprehensive. A gun that does not appear in one of them could still be stolen; it just means the owner did not report it to that particular site. Treat a clean result from a private site as a supplement, not a substitute for an NCIC check through law enforcement or a licensed dealer.
When There Is No Serial Number, or It Looks Altered
Not every firearm has a serial number, and the reason matters.
The Gun Control Act of 1968 was the first federal law to require licensed manufacturers and importers to mark every firearm with a serial number.5Federal Register. Identification Markings Placed on Firearms Serialization was common industry practice before then but not required, so some older firearms were legitimately never numbered. Owning one is legal. The ATF Form 4473 used for dealer sales tells dealers to enter “NSN” (No Serial Number), “N/A,” or “None” when transferring a legally unserialized firearm.6Bureau of Alcohol, Tobacco, Firearms and Explosives. Firearms Transaction Record
A firearm you build at home for personal use also does not need a serial number under federal law, as long as you are not in the business of manufacturing firearms for sale.7Bureau of Alcohol, Tobacco, Firearms and Explosives. Privately Made Firearms That changes when the gun enters the commercial stream. If you bring an unserialized homemade gun to a licensed dealer for consignment, trade-in, or repair that involves taking it into inventory, the dealer must mark it with a serial number within seven days or before selling it, whichever comes first.8Bureau of Alcohol, Tobacco, Firearms and Explosives. Summary of Final Rule 2021R-05F Some states impose additional requirements on privately made firearms, so check your state’s rules.
A gun that never had a number is one thing. A gun whose number has been removed, scratched out, or altered is another. Federal law makes it a crime to knowingly ship, transport, receive, or possess a firearm with a defaced serial number.9Office of the Law Revision Counsel. 18 USC 922 – Unlawful Acts The penalty is up to five years in federal prison, a fine, or both.10Office of the Law Revision Counsel. 18 USC 924 – Penalties “Knowingly” is doing real work in that statute: a prosecutor has to prove you knew the number had been tampered with.
If you find a firearm with a scratched-out, filed-down, or suspiciously altered serial number, do not clean it, polish it, or try to restore it yourself. Contact local law enforcement for guidance. Forensic examiners have methods for recovering defaced numbers from the deeper metal, and a well-meaning DIY effort can destroy the evidence they would use.
Write Down What You Find
The ATF recommends that every firearm owner keep a personal record of each gun they own, stored separately from the firearms themselves.11Bureau of Alcohol, Tobacco, Firearms and Explosives. Personal Firearms Record The reasoning is simple: if a gun is stolen and you cannot give police the serial number, the odds of recovery drop sharply.
For each firearm, record the manufacturer, model, serial number, type (pistol, rifle, shotgun), caliber or gauge, date acquired, price, and where you bought it.11Bureau of Alcohol, Tobacco, Firearms and Explosives. Personal Firearms Record If you sell or transfer a firearm, note the buyer’s name and address and the date. Keep the record in a safe, a lockbox, or a secure digital file, and not in the same place as the guns. For a private sale, a bill of sale that includes the serial number protects both sides and documents when the gun changed hands.