To legally own a gun in the United States, you need to meet federal age and eligibility rules, pass a background check when you buy from a licensed dealer, and follow any extra requirements your state imposes on top of that federal baseline.1Congress.gov. The Gun Control Act of 1968 (GCA, 18 USC 921) The federal floor is the same everywhere. What sits above it changes at every state line.
Who Qualifies Under Federal Law
The Gun Control Act of 1968 sets the national eligibility rules, and the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) enforces them.2Bureau of Alcohol, Tobacco, Firearms and Explosives. Firearms Two things determine whether you can legally own a firearm: your age and whether you fall into any prohibited category.
Age
A licensed dealer cannot sell you a handgun or handgun ammunition if you are under 21. For rifles, shotguns, and their ammunition, the minimum is 18.1Congress.gov. The Gun Control Act of 1968 (GCA, 18 USC 921) Some states set the age higher, so confirm your state’s rule before assuming you qualify.
Prohibited Persons
Under 18 U.S.C. § 922(g), you cannot legally possess a firearm or ammunition if you:
- Have been convicted of a crime punishable by more than one year in prison, whether or not you actually served that long
- Are a fugitive from justice
- Use or are addicted to a controlled substance, including marijuana even in states where it is legal under state law
- Have been adjudicated as mentally defective or committed to a mental institution
- Are in the country unlawfully, or hold a nonimmigrant visa without a qualifying exception such as a valid state hunting license
- Were dishonorably discharged from the military
- Have renounced U.S. citizenship
- Are subject to a qualifying domestic restraining order issued after a hearing you had notice of and a chance to attend
- Have been convicted of a misdemeanor crime of domestic violence
These bars apply nationwide. If any one of them fits you, possessing even a single round of ammunition is a federal crime.3Office of the Law Revision Counsel. 18 USC 922 – Unlawful Acts
Buying From a Licensed Dealer
The clean legal path to owning a gun runs through a Federally Licensed Firearms Dealer (FFL). The sequence is the same at every dealer: show ID, fill out the federal form, wait for the background check.
Identification
Bring a valid government-issued photo ID that shows your name, date of birth, residence address, and photograph. A driver’s license or state ID is standard. If the address on your ID is outdated, a recent utility bill or vehicle registration can fill the gap.4Bureau of Alcohol, Tobacco, Firearms and Explosives. Federal Firearms Licensee Quick Reference and Best Practices Guide
ATF Form 4473
You fill out ATF Form 4473, the Firearms Transaction Record, at the dealer’s premises. It collects your biographical information and walks through yes-or-no questions that mirror the prohibited-person categories: felony convictions, drug use, domestic violence history, and the rest. The dealer records the firearm’s make, model, and serial number.5Bureau of Alcohol, Tobacco, Firearms and Explosives. Firearms Transaction Record – ATF Form 4473
Lying on Form 4473 is a federal felony carrying up to 15 years in prison and a $250,000 fine. The penalty applies even if the false answer would not have changed the outcome of the sale.5Bureau of Alcohol, Tobacco, Firearms and Explosives. Firearms Transaction Record – ATF Form 4473
The NICS Background Check
The dealer submits your information to the National Instant Criminal Background Check System (NICS), created by the Brady Handgun Violence Prevention Act of 1993 and run by the FBI.6Federal Bureau of Investigation. About NICS NICS checks federal and state criminal records, mental health records, and other databases, then returns one of three responses: Proceed, Denied, or Delayed.
Delayed means examiners need more time. For buyers 21 and older, if no final answer comes back within three business days, the dealer may (but is not required to) complete the sale.7Federal Bureau of Investigation. NICS Firearms Licensee Manual For buyers between 18 and 20, the Bipartisan Safer Communities Act extended the review window to up to ten business days so examiners can check state juvenile justice, mental health, and local law enforcement records that don’t show up in the standard databases.8Federal Bureau of Investigation. NICS Enhanced Background Checks for Under-21 Gun Buyers Showing Results
A denial can be challenged. The FBI accepts appeals electronically and is required to respond within 60 calendar days.9Federal Bureau of Investigation. Challenges / Appeals
Don’t Buy a Gun for Someone Else
One of the first questions on Form 4473 asks whether you are the actual buyer. If someone else hands you cash and sends you to a dealer to buy a gun for them, that is a straw purchase, and it is a federal crime for both people. The penalty is up to 15 years in prison and a $250,000 fine, rising to 25 years if the firearm is later used in a felony, an act of terrorism, or a drug trafficking crime.10Bureau of Alcohol, Tobacco, Firearms and Explosives. Don’t Lie for the Other Guy Buying a firearm as a legitimate gift is legal. What matters is whether you are using your own money and making your own decision to give it, and whether the recipient could legally pass a background check themselves.
Private Sales Between Individuals
Federal law does not require private sellers to run a background check on intrastate sales between two residents of the same state. Some states have closed this gap by requiring all sales, including private ones, to route through a licensed dealer.
Even where private sales are unregulated, it remains a federal crime to sell or give a firearm to someone you know or have reasonable cause to believe is a prohibited person.3Office of the Law Revision Counsel. 18 USC 922 – Unlawful Acts Many private sellers protect themselves by asking to see a concealed carry permit or by routing the transfer through an FFL anyway.
If you repeatedly buy and resell firearms to earn a profit, the ATF considers you engaged in the business of dealing firearms and you need an FFL, regardless of how many guns you move or where you sell them.11Bureau of Alcohol, Tobacco, Firearms and Explosives. Federal Firearms Licenses
What Your State Adds
Federal law is the floor, not the ceiling. Depending on where you live, your state may add several layers on top.
Purchase Permits and Owner ID Cards
Some states require you to obtain a purchase permit or firearm owner identification card before you can buy. The process usually runs through a local law enforcement agency and involves fingerprints and a state-level background check that may go beyond NICS. Some states apply this requirement only to handguns; others cover all firearms.
Waiting Periods
Several states impose a mandatory waiting period between purchase and possession, typically ranging from a few days to over a week. In states that also require a purchase permit, the application process itself can add weeks of built-in delay.
Bans on Specific Firearms and Features
Some states ban categories of firearms outright or restrict features like magazine capacity above a certain number of rounds. A gun that is legal to own in one state can be a felony to possess in the state next door. If you move or travel, checking your firearms against the destination state’s laws is on you.
Extreme Risk Protection Orders
More than 20 states have extreme risk protection order (ERPO) laws, sometimes called red flag laws. Family members, law enforcement, or in some states other concerned individuals can petition a court to temporarily remove firearms from someone who poses a danger to themselves or others. A judge can issue a temporary order on an emergency basis, followed by a hearing where the person can respond, and if the court finds sufficient risk, an extended order can bar purchase or possession for a set period.
NFA-Regulated Firearms Follow a Different Process
Some firearms and accessories are regulated under the National Firearms Act (NFA) of 1934 and do not follow the standard dealer purchase process. NFA items include machine guns (civilian ownership is limited to those manufactured and registered before May 1986), short-barreled rifles, short-barreled shotguns, suppressors, and destructive devices such as grenades and firearms with a bore over half an inch (with exceptions for sporting shotguns). The definitions live at 26 U.S.C. § 5845.12Office of the Law Revision Counsel. 26 US Code 5845 – Definitions
To acquire one, you file ATF Form 4, submit fingerprints, pass a background check, and wait for ATF approval before taking possession.13Bureau of Alcohol, Tobacco, Firearms and Explosives. Application for Tax Paid Transfer and Registration of Firearms – ATF Form 4 (5320.4) The historical $200 tax stamp was eliminated effective January 2026 for suppressors and short-barreled rifles, but registration itself is still mandatory, and approval can take several months. Possessing an unregistered NFA item is a serious federal crime. Some states prohibit civilian ownership of certain NFA items entirely, and ATF approval does not override a state ban.
Carrying in Public Is a Separate Question
Owning a firearm and carrying it outside your home are treated as different legal issues in most states. Owning a legally purchased firearm at home does not automatically permit you to carry it in public. Roughly 29 states allow permitless (or “constitutional”) carry for residents who are otherwise eligible to own; the rest require a concealed carry permit with its own application, background check, and often a safety course. There is no federal law requiring states to honor each other’s carry permits, so reciprocity is a state-by-state patchwork.
One federal restriction catches otherwise careful owners off guard: the Gun-Free School Zones Act makes it a felony to possess a firearm within 1,000 feet of an elementary or secondary school, with exceptions for state-licensed carriers, private property outside school grounds, and firearms that are unloaded and in a locked container.14Office of the Law Revision Counsel. 18 US Code 922 – Unlawful Acts School zones cover more ground than most people picture, particularly in built-up neighborhoods.
What Owning a Gun Requires After the Sale
Safe Storage
A large number of states have Child Access Prevention (CAP) laws that impose criminal penalties on owners if a minor gains access to a negligently stored firearm. Penalties range from misdemeanors to felonies depending on the state and whether anyone was hurt. A gun safe, locking steel cabinet, or trigger lock all qualify as secure storage.
Transporting Firearms Between States
Federal law offers a safe-passage protection at 18 U.S.C. § 926A. You may transport a firearm through any state as long as you can legally possess it at both the start and end of your trip, the gun is unloaded, and neither the firearm nor the ammunition is readily accessible from the passenger compartment. In vehicles without a separate trunk, both must be in a locked container other than the glove compartment or console.15Office of the Law Revision Counsel. 18 USC 926A – Interstate Transportation of Firearms
The protection covers transit only. Overnight stops or extended breaks can put you outside its coverage in the eyes of states with strict firearm laws, and travelers have been arrested at intermediate stops even when their trip began and ended in states where the gun was legal.
NFA items require separate advance written approval from the ATF on Form 5320.20 before crossing state lines. The application specifies the dates and destination, and the approved form must travel with the item.16Bureau of Alcohol, Tobacco, Firearms and Explosives. Application to Transport Interstate or to Temporarily Export Certain National Firearms Act (NFA) Firearms
Lost or Stolen Firearms
Reporting a lost or stolen firearm to local law enforcement creates a record that helps trace the gun if it is recovered and protects you if it later surfaces at a crime scene. Licensed dealers have a federal obligation to report theft or loss to both the ATF and local police within 48 hours of discovery.17Bureau of Alcohol, Tobacco, Firearms and Explosives. Report Firearms Theft or Loss Individual owners are not subject to the same federal mandate, but a growing number of states have enacted their own reporting requirements with criminal penalties for failure to comply.