NICS Background Check: Process, Responses, and Denials

A NICS background check is the screening the FBI runs through the National Instant Criminal Background Check System whenever you try to buy a firearm from a licensed dealer. The dealer submits your identifying information from ATF Form 4473, the system searches three federal databases, and in most cases the dealer gets a Proceed, Denied, or Delayed response within minutes.¹ Congress created the system through the Brady Handgun Violence Prevention Act of 1993, and the FBI processed more than 28 million firearm-related checks through it in 2024.²

One boundary matters up front. Federal law only requires a NICS check when the seller is a licensed importer, manufacturer, or dealer.³ Private sales between individuals who aren’t licensed dealers aren’t covered by the federal requirement, though roughly 20 states and the District of Columbia have closed that gap in their own laws.

What You Do at the Counter

Every purchase from a licensed dealer starts with ATF Form 4473, the Firearms Transaction Record. You complete it at the dealer’s place of business.⁴ The form asks for your full legal name, current home address, place of birth, and physical descriptors like height, weight, and race, all of which help the FBI match you accurately against records.

You have to show a valid government-issued photo ID with your name, address, and date of birth. If your photo ID doesn’t show your current address, you can supplement it with another government-issued document that does, including a valid electronic document from a government website.⁴ The Social Security number field is optional. Providing it is worth considering because it helps distinguish you from other people with similar names and reduces the chance of a delay caused by misidentification.

Lying on Form 4473 is a federal felony punishable by up to five years in prison.⁵ Once you’ve signed, the dealer contacts the NICS Section, either through the FBI’s E-Check online system or by calling a NICS examiner directly.

What the FBI Actually Searches

The system automatically scans three databases for matches against your identifying information:

The National Crime Information Center (NCIC), which holds records on active warrants, protection orders, and immigration status, and flags people prohibited from possessing firearms due to specific civil or criminal court actions.
The Interstate Identification Index (III), a national pointer system that pulls state-level criminal history records to check for felony convictions and serious misdemeanors.
The NICS Index, which contains records on people specifically prohibited under federal or state law when the disqualifying information wouldn’t show up in the other two databases, often mental health adjudications or dishonorable military discharges.

The digital search takes seconds. When it flags a potential match, a human examiner steps in to review manually so you aren’t confused with someone who happens to share your name or date of birth.

The Three Responses You Can Get

The FBI gives the dealer one of three answers. In 2024, about 94.7% of checks handled by the FBI’s NICS Section came back as immediate approvals, and about 1.1% ended in a denial.²

Proceed. No disqualifying records were found and the dealer can complete the sale.
Denied. A record showed you’re legally prohibited from possessing a firearm and the dealer cannot complete the transfer.
Delayed. The FBI needs more time to research a potential record before deciding.

The Three-Business-Day Rule for Delays

If your check is delayed, the FBI has three business days from the date the dealer contacted the system to issue a final response. If no response comes by then, the dealer has legal discretion to go ahead and transfer the firearm.³ This is often called the Brady transfer date. Federal law permits the transfer at that point, but not every dealer will proceed. Some store policies and some state laws require waiting for a definitive answer.

Extra Rules if You’re Under 21

The Bipartisan Safer Communities Act of 2022 added a longer process for buyers under 21. The FBI has to contact three additional agencies: the state criminal history or juvenile justice repository, the state custodian of mental health adjudication records, and the buyer’s local law enforcement agency.⁶ These inquiries look for disqualifying juvenile records that wouldn’t appear in the standard databases.

The FBI gets three business days to decide whether there’s cause for further investigation into a juvenile record. If cause exists, the FBI notifies the dealer and the transfer is paused. From that point the dealer cannot complete the sale until the FBI issues a Proceed response or 10 business days have elapsed from the original contact, whichever comes first.³

Who Federal Law Prohibits From Buying

Federal law identifies specific categories of people who cannot legally possess firearms or ammunition. A match in any of these categories is what produces a Denied response:⁷

Anyone convicted of a crime punishable by more than one year in prison, which covers most felonies and some high-level misdemeanors depending on state classification.
Fugitives from justice, meaning anyone with an active warrant.
Anyone who currently uses or is addicted to a controlled substance.
Anyone formally adjudicated as mentally incompetent or involuntarily committed to a mental institution.
Anyone subject to a qualifying domestic violence restraining order.
Anyone convicted of a misdemeanor crime of domestic violence.
Anyone dishonorably discharged from the military.
Anyone who has renounced their U.S. citizenship.
Anyone unlawfully present in the United States.

For state convictions, rights can sometimes be restored through state-level mechanisms like pardons, expungements, or formal restoration proceedings. Federal convictions are different. There is no general federal expungement process, and restoring firearm rights after a federal conviction requires a presidential pardon.

What to Do if You’re Denied

A denial doesn’t always mean the system got it right. Mistaken identity, outdated records, and data-entry errors all cause erroneous denials. You have two administrative options before going to court.⁸

First, you can ask the FBI to explain why you were denied. You’ll need your name, mailing address, phone number, and the NICS Transaction Number (NTN) or State Transaction Number (STN) from the transaction. You can submit the request through the FBI’s Electronic Departmental Order system or by mail, and the FBI must respond within five business days.

Second, you can submit a formal challenge if you believe the denial was based on incorrect information. The FBI must respond within 60 calendar days with a final decision to sustain or overturn the denial. Submitting fingerprints with your challenge isn’t required, but the FBI strongly encourages it, especially if you have a common name, because prints can quickly confirm or rule out identity matches. Only denials can be challenged this way; a Delayed status cannot.

If the administrative process doesn’t fix it, federal law allows you to file a civil lawsuit seeking a court order to correct the record or approve the transfer, and the court can award attorney’s fees to the prevailing party.⁹ The FBI also runs a Voluntary Appeal File (VAF) for people who have been wrongly denied or repeatedly delayed. Once approved, you receive a Unique Personal Identification Number (UPIN) that you can enter on Form 4473 for future purchases to help prevent repeated problems.¹⁰

How Long the FBI Keeps Your Information

Federal regulations tightly limit retention. For approved transactions, the FBI must destroy all identifying information within 24 hours after the dealer receives the Proceed response. Most other transaction data, except the NICS Transaction Number and date, must be destroyed within 90 days.¹¹ The rapid destruction policy exists specifically to prevent the system from becoming a registry of lawful gun owners. Your dealer, though, keeps the completed Form 4473 at their place of business for at least 20 years under ATF regulations.

1
Federal Bureau of Investigation. Firearms Checks (NICS)
2
Federal Bureau of Investigation. 2024 NICS Operational Report
3
Office of the Law Revision Counsel. 18 USC 922 – Unlawful Acts
4
Bureau of Alcohol, Tobacco, Firearms and Explosives. ATF Form 4473 – Firearms Transaction Record
5
Office of the Law Revision Counsel. 18 USC 924 – Penalties
6
Federal Bureau of Investigation. NICS Enhanced Background Checks for Under-21 Gun Buyers Showing Results
7
Office of the Law Revision Counsel. 18 USC 922 – Unlawful Acts
8
Federal Bureau of Investigation. Requesting Reason for and/or Challenging a NICS-Related Denial
9
Office of the Law Revision Counsel. 18 USC 925A – Remedy for Erroneous Denial of Firearm
10
Federal Bureau of Investigation. Voluntary Appeal File (VAF)
11
eCFR. 28 CFR 25.9 – Retention and Destruction of Records in the System