Gun Laws in America: Federal Rules, State Limits, and Carry

Gun laws in America run on two tracks. Federal law sets the national floor: who is barred from having a firearm, what weapons require special registration, and what checks apply at the point of sale. State law adds the rest: purchase permits, waiting periods, carry rules, magazine limits, and restrictions on specific weapon types. A transaction that is perfectly legal in one state can be a serious felony a mile across the state line, so knowing both layers matters.

Who Can Legally Own a Firearm

Federal law bars nine categories of people from possessing any firearm or ammunition, anywhere in the country. The list comes from 18 U.S.C. § 922(g) and covers:¹

Anyone convicted of a crime punishable by more than one year in prison.
Fugitives from justice.
Unlawful users of, or people addicted to, a controlled substance.
People adjudicated as mentally defective or committed to a mental institution.
People unlawfully in the United States, and most nonimmigrant visa holders.
Anyone dishonorably discharged from the military.
Former U.S. citizens who have renounced their citizenship.
People subject to a qualifying domestic violence restraining order.
People convicted of a misdemeanor crime of domestic violence.

That last category, sometimes called the Lautenberg Amendment, is the one that catches people off guard. A misdemeanor conviction, not a felony, can permanently strip firearm rights.

Age floors sit on top of the prohibited-person list. To buy from a licensed dealer, you must be at least 18 for a rifle or shotgun and at least 21 for a handgun or handgun ammunition.¹ Private transfers have a lower floor under federal law (no handgun to anyone under 18, no age minimum for long guns), but many states set their own higher limits.

How Buying a Firearm Works

The Gun Control Act of 1968 is the main federal statute governing firearms commerce, and the Bureau of Alcohol, Tobacco, Firearms and Explosives enforces it.² Anyone in the business of selling firearms must hold a Federal Firearms License (FFL).

The Background Check

Every time an FFL transfers a firearm to an unlicensed buyer, the dealer runs the buyer through the National Instant Criminal Background Check System (NICS), operated by the FBI. NICS screens against criminal history, mental health, and other databases to decide whether the buyer is legally allowed to have a firearm.³

Most checks return an answer within minutes. When they don’t, federal law allows the dealer to complete the sale if NICS has not issued a denial within three business days. That default-proceed rule keeps buyers from waiting indefinitely, but it means a small number of sales close before the check is fully resolved.

Buyers Under 21

The Bipartisan Safer Communities Act of 2022 added enhanced review for buyers under 21. NICS now contacts state juvenile justice and mental health repositories, plus local law enforcement, to check for disqualifying juvenile records. If those searches flag something, the review can run up to ten business days before the sale can proceed.⁴

Private Sales

Federal law does not require a background check when two unlicensed individuals in the same state complete a private sale. The seller still cannot knowingly transfer a firearm to a prohibited person, but private sellers have no access to NICS and no reliable way to verify a buyer’s status on their own.³ About 20 states have closed this gap by requiring background checks on all or most private transfers.

Interstate private sales are prohibited without a dealer’s involvement. If the buyer lives in a different state, the firearm must be shipped to an FFL in the buyer’s state, where the buyer picks it up and completes a standard NICS check.³

Weapons That Require Federal Registration

Some weapons need more than a background check. The National Firearms Act of 1934 imposes a $200 tax on the making and transfer of covered items and requires each one to be registered in a federal database. That $200 figure has not moved since 1934.⁵

NFA-regulated items include:

Short-barreled rifles: barrel under 16 inches, or overall length under 26 inches.
Short-barreled shotguns: barrel under 18 inches, or overall length under 26 inches.
Machine guns, meaning firearms that fire more than one round per trigger pull, plus conversion parts and kits.
Silencers (suppressors) and their component parts.
Destructive devices, including grenades, bombs, and weapons with a bore over half an inch (standard shotguns excepted).

The registration rule has no back door. If an NFA item was never registered, there is no way to register it now, and possessing an unregistered NFA item is a federal felony.⁵ Machine guns carry a further limit: the Firearm Owners’ Protection Act of 1986 banned civilian transfer or possession of machine guns manufactured after May 19, 1986. Only pre-1986 registered machine guns can still change hands.

Where State Law Changes the Picture

Federal law is the floor. State law is where the real variation lives.

Purchase Permits and Waiting Periods

Some states require a special permit or identification card before you can buy a firearm at all. Illinois requires a Firearm Owner’s Identification card for anyone possessing firearms or ammunition. Other states have permit-to-purchase requirements limited to handguns, long guns, or both, each with its own background check and application process separate from the federal NICS check.

About a dozen states and the District of Columbia require a waiting period between purchase and delivery, running from 72 hours to 14 days depending on the state and the weapon. Some cover all firearms; others apply only to handguns or certain semi-automatic weapons.

Assault Weapons and Magazine Limits

Ten states ban certain semi-automatic firearms classified as “assault weapons,” typically defined by a combination of features (pistol grips, folding stocks, threaded barrels, and the like) paired with the ability to accept detachable magazines. Several of these states also cap magazine capacity, most commonly at 10 rounds. These laws are being actively challenged in court, and their future is unsettled.

Red Flag Laws

More than 20 states and the District of Columbia have Extreme Risk Protection Orders, often called red flag laws. A court can temporarily bar someone from possessing firearms when a petition (usually from law enforcement or a family member) shows the person poses a danger. These are civil orders, they run for a set period, and the person subject to the order can request a hearing to contest it.

Safe Storage

Roughly half the states impose some form of liability on gun owners who fail to secure firearms from minors. The strictest versions apply whenever a child is likely to gain access to an unsecured gun. The weakest versions kick in only if a child actually obtains and uses the firearm to cause harm. Penalties range from misdemeanor fines to felony charges.

Carrying Firearms in Public

Concealed carry is the biggest area of state-to-state variation. States fall into three groups:

Shall-issue states must grant a carry permit to anyone who meets objective criteria such as a background check and training. Officials have no discretion to deny a qualified applicant.
May-issue states let officials deny a permit even to someone who meets the baseline requirements, often by demanding a special reason for needing to carry.
Constitutional carry (or permitless carry) states require no permit at all. Anyone who can legally possess a firearm can carry it concealed.

The map has shifted heavily toward permitless carry. As of 2025, 29 states allow some form of it, up from a handful a decade ago. Most of these states still issue permits for residents who want them, mainly so they can carry when traveling to states that honor the permit through reciprocity.

The Supreme Court’s 2022 decision in New York State Rifle & Pistol Association v. Bruen struck down New York’s requirement that concealed carry applicants show a “special need” different from the general public. The Court held that the Second Amendment protects a right to carry a handgun in public for self-defense that cannot be conditioned on proving unusual danger.⁶ Remaining may-issue states have had to move toward objective criteria, though some have responded by tightening the requirements they can still impose, such as training hours and expanded lists of sensitive places where carry remains off-limits.

Crossing State Lines With a Firearm

Interstate travel is where careful gun owners get caught. The Firearm Owners’ Protection Act includes a “safe passage” provision at 18 U.S.C. § 926A that lets you transport a firearm from one state where you may legally possess it to another state where you may legally possess it, regardless of the laws in between, if you follow the rules:⁷

The firearm must be unloaded.
Neither the firearm nor any ammunition can be readily accessible from the passenger compartment.
In vehicles without a separate trunk, the firearm and ammunition must be in a locked container other than the glove compartment or console.

The protection covers you while in transit. Stop in a restrictive state for anything beyond fuel, food, or rest and its coverage becomes uncertain. Travelers have been arrested at New York and New Jersey airports after cancelled flights forced them to retrieve checked bags containing firearms and re-enter a state where those firearms were illegal. Courts have generally read FOPA narrowly in those situations. If your route runs through a strict jurisdiction, plan for the disruption, not just the smooth trip.

Flying With a Firearm

Firearms are allowed in checked baggage under specific TSA rules. The firearm must be unloaded and locked in a hard-sided container that fully prevents access. You must declare it to the airline at the ticket counter every time you check the bag, and only you should hold the key or combination.⁸

Ammunition may go in checked baggage in packaging designed for it, such as the original box. Loaded magazines must be securely boxed or stored inside the locked hard-sided case with the unloaded firearm. Nothing firearm-related is allowed in carry-on bags.⁸

Declaring the firearm to TSA does not override the laws of your destination. Before booking, confirm your firearm is legal in every jurisdiction where you might have to collect your luggage, including any layover city where a missed connection could leave you overnight.

Penalties for Getting It Wrong

Federal firearms penalties are heavy, and they have grown in recent years. A prohibited person caught with a firearm faces up to 15 years in federal prison, increased from 10 years by the Bipartisan Safer Communities Act.⁹

Lying on the ATF Form 4473 background check form is its own felony, punishable by up to 10 years. The form asks about criminal history, drug use, immigration status, and mental health, and false answers to any of them qualify.⁹

Straw purchasing, buying a firearm on behalf of someone who cannot legally buy one, carries up to 15 years and a $250,000 fine. If the firearm is used in a felony, terrorist act, or drug trafficking offense, the maximum climbs to 25 years.¹⁰ Dealing firearms without a license carries up to five years. Using or carrying a firearm during a federal drug trafficking offense or violent crime triggers mandatory minimums of five to 30 additional years on top of the sentence for the underlying crime.⁹

1
Office of the Law Revision Counsel. 18 USC 922 – Unlawful Acts
2
Bureau of Alcohol, Tobacco, Firearms and Explosives. Gun Control Act
3
Bureau of Alcohol, Tobacco, Firearms and Explosives. Federal Firearms Licensee Quick Reference and Best Practices Guide
4
Congress.gov. Text – Bipartisan Safer Communities Act
5
Bureau of Alcohol, Tobacco, Firearms and Explosives. National Firearms Act
6
Supreme Court of the United States. New York State Rifle and Pistol Association Inc. v. Bruen
7
Office of the Law Revision Counsel. 18 USC 926A – Interstate Transportation of Firearms
8
Transportation Security Administration. Transporting Firearms and Ammunition
9
Office of the Law Revision Counsel. 18 USC 924 – Penalties
10
Office of the Law Revision Counsel. 18 USC 932 – Straw Purchasing of Firearms