What Guns Are Banned in the United States? Federal and State Laws Explained

There is no single list of guns banned everywhere in the United States. Federal law prohibits certain firearms and restricts others, while state and local laws may impose additional bans based on a gun’s features, model, or magazine capacity. The rules can also depend on who possesses the firearm and how it is transferred. Understanding the difference between a prohibited firearm and a regulated one is essential: a machine gun is generally barred from civilian transfer if made after 1986, while a suppressor is regulated under federal law but is not categorically banned nationwide.

There Is No One Nationwide List of Banned Guns

Firearm laws in the United States operate at multiple levels. Federal statutes set nationwide rules, and states may enact stricter restrictions. Some cities and counties have additional requirements, although state preemption laws can limit local authority. As a result, a firearm that is legal to possess in one state may be prohibited or restricted in another.

The word “banned” also has several meanings. A law might prohibit possession of a firearm, prohibit its sale or transfer, restrict a specific feature, or require registration and special tax treatment. A firearm can be legal to own under federal law but still illegal under a state law—or legal only if its owner complies with applicable registration and transfer rules.

The following overview describes major categories under federal law and common types of state restrictions. It is general information, not legal advice. Laws and court rulings change, so current federal, state, and local rules should be checked before acquiring, transporting, or modifying a firearm.

Firearms Prohibited or Restricted Under Federal Law

Machine guns

Federal law generally bars civilians from possessing or transferring machine guns made after May 19, 1986, except for government use and certain other limited circumstances. A machine gun is defined broadly in federal law: it includes a firearm that fires more than one shot automatically, without manual reloading, by a single function of the trigger. The definition also covers certain conversion parts and combinations of parts designed to convert a firearm into a machine gun.

Some machine guns made and registered before the cutoff date may still be possessed and transferred by eligible people under the National Firearms Act (NFA), subject to federal approval and other requirements. These are not ordinary over-the-counter purchases. State law may prohibit machine guns altogether, including older registered ones. A firearm’s appearance alone does not determine its legal classification; its design and operation matter.

Short-barreled rifles and shotguns

The NFA regulates certain short-barreled rifles and shotguns. Federal definitions generally cover a rifle with a barrel shorter than 16 inches, a shotgun with a barrel shorter than 18 inches, and some firearms modified to fall below specified overall-length limits. These firearms are not uniformly banned under federal law, but making or transferring an NFA-regulated firearm generally requires prior approval and registration under federal procedures. State laws may prohibit them or impose additional restrictions.

Classification can depend on how a firearm is configured. Removing a stock, changing a barrel, or combining parts in a particular way may affect its legal status. Because a seemingly small modification can create a regulated firearm, owners should confirm the classification and required approvals before making changes.

Destructive devices and certain explosive weapons

Federal law defines “destructive devices” to include certain explosive, incendiary, or poison-gas weapons, as well as specified large-bore weapons and components. The statutory definition includes devices such as bombs and grenades, and generally covers weapons with a bore over one-half inch that are not recognized as ordinary sporting firearms or suitable for sporting purposes. The precise legal classification depends on the device and applicable law.

Destructive devices are subject to federal controls, including NFA rules, and may be prohibited by state law. The definition has exceptions and technical details, so it should not be reduced to a simple rule that every firearm over a particular caliber is illegal.

Unregistered NFA firearms

Some items are regulated rather than banned, but possessing them without complying with federal requirements can be unlawful. The NFA covers machine guns, short-barreled rifles, short-barreled shotguns, silencers (commonly called suppressors), destructive devices, and certain other firearms. Depending on the item and transaction, federal law may require registration, prior approval, and payment of a tax.

A suppressor is therefore not banned nationwide under federal law, but it is restricted and is illegal to possess or transfer outside the required legal process. Some states prohibit civilian suppressor ownership; others allow it under federal and state rules. The same distinction—regulated does not mean universally banned—applies to many NFA firearms.

Undetectable firearms and prohibited devices

The federal Undetectable Firearms Act prohibits manufacturing, importing, selling, shipping, delivering, possessing, transferring, or receiving firearms that meet the law’s definition of “undetectable,” with limited statutory exceptions. The law addresses firearms that are not detectable by specified security equipment, as well as certain firearm components. This is a technical legal standard; it does not mean that every firearm containing plastic or produced with a 3D printer is automatically illegal.

Federal law also regulates certain firearm parts and devices, including machine-gun conversion devices. A component can fall under a firearm definition even when it is not a complete, assembled gun. Because parts-based cases depend on statutory definitions and technical facts, a person should not assume that a small component is unregulated.

State “Assault Weapon” Bans and Feature Restrictions

Several states and the District of Columbia restrict or prohibit firearms they define as “assault weapons.” There is no single federal definition that controls all state laws. Depending on the jurisdiction, a law may identify firearms by make and model, by a combination of features, or by both methods. Restrictions may cover semiautomatic rifles, pistols, or shotguns with specified characteristics.

Feature-based laws commonly refer to elements such as a folding or telescoping stock, a pistol grip, a flash suppressor, a forward grip, or a threaded barrel. The exact list and how features are counted vary. A firearm that is legal in one state may be prohibited in another even if it has the same basic action and caliber.

Some state laws allow continued possession of certain firearms owned before a cutoff date, but may require registration, limits on transfer, or other conditions. Others prohibit possession or transfer more broadly. A grandfather clause should never be assumed: its scope, deadlines, documentation requirements, and exceptions depend on the law in effect where the owner lives.

High-Capacity Magazine Restrictions

Magazine capacity limits are often discussed alongside gun bans, but a magazine is not itself a firearm. Some states and the District of Columbia restrict magazines above a specified capacity, commonly using a threshold such as 10 rounds. Other states do not impose a general statewide limit. Laws may regulate possession, sale, importation, manufacture, or transfer differently, and exceptions may apply.

Whether a magazine is legal can depend on when it was acquired, how it is configured, and whether the law allows possession of older magazines. These rules can also affect travel: bringing a magazine across a state line may create a legal issue even when the firearm itself is lawful. The current statute and any applicable court orders should be reviewed before transporting magazines.

Firearms That Are Legal for Some People but Not Others

Federal law prohibits certain people from possessing firearms, regardless of the firearm’s model. Categories include people convicted of qualifying felonies, fugitives from justice, unlawful users of or people addicted to controlled substances, and people subject to certain qualifying domestic-violence restraining orders or misdemeanor convictions. The federal prohibitions are detailed, and exceptions or restoration procedures may apply in some circumstances.

Other restrictions concern immigration status, certain mental-health adjudications or commitments, and specified military discharges. State laws can add further prohibited categories. A person’s eligibility can depend on the exact court record, the nature of a conviction, and whether rights have been restored. It is not safe to determine eligibility from a broad label alone.

These person-based restrictions do not mean that a particular firearm is banned for everyone. They mean that possession or receipt by a specific person may be unlawful. Federal law also generally prohibits knowingly transferring a firearm to someone the transferor knows or has reasonable cause to believe is prohibited.

Other Federal Restrictions That Affect Certain Guns

Import restrictions

Federal law restricts the importation of certain firearms that do not qualify for import under applicable statutory standards, including rules concerning sporting purposes. Import rules are complex and can involve the firearm’s design, parts, and intended use. An imported firearm’s legal status may differ from that of a similar firearm manufactured domestically, but import restrictions do not create a simple nationwide list of every prohibited model.

Unlicensed manufacture and homemade firearms

Federal law does not generally ban every privately made firearm. However, manufacturing, dealing, or importing firearms can trigger federal licensing and other obligations, and state laws may impose separate requirements. Rules concerning serial numbers, records, background checks, and unfinished receivers vary by jurisdiction and have changed through legislation and regulation.

A privately made firearm is not automatically exempt from laws governing prohibited persons, machine guns, NFA items, or state assault-weapon restrictions. A firearm’s method of manufacture does not erase the legal rules that apply to its design and possession.

Firearms with altered serial numbers

Federal law generally prohibits possessing or receiving a firearm with a serial number that has been removed, obliterated, or altered, subject to statutory details and exceptions. State laws may also address defaced or missing serial numbers. A firearm with a damaged marking can raise legal questions even if the owner did not alter it, so the circumstances and governing law matter.

How to Check Whether a Specific Gun Is Banned

Before buying, selling, modifying, or traveling with a firearm, the relevant question is not simply whether “guns like it” are legal. The answer may depend on the exact model, configuration, magazine, state of residence, transfer method, and the owner’s legal eligibility.

1. Identify the firearm precisely. Record the manufacturer, model, action type, caliber, barrel length, overall length, and attached features. Note any relevant parts or magazines.
2. Check federal classification. Consult the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) guidance for federal definitions, NFA procedures, and firearm classifications. For an NFA item, verify approval and registration requirements before taking possession or making changes.
3. Read the law where the firearm will be possessed. Review state statutes and official state police, attorney general, or licensing-agency guidance. Check local rules where relevant and determine whether state preemption applies.
4. Verify transfer and travel rules. Laws can differ for purchases, private transfers, temporary possession, and transport through another state. Confirm requirements before crossing state lines.
5. Get qualified legal advice when the facts are uncertain. Firearm definitions can turn on technical details, and a mistaken modification or transfer can carry serious consequences.

Key Takeaways

• Federal law does not ban every firearm commonly described as an assault weapon. State definitions and restrictions differ substantially.
• Most civilian transfers of post-1986 machine guns are prohibited under federal law. Some pre-1986 registered machine guns may be transferable under strict rules, unless state law forbids them.
• Suppressors and many short-barreled firearms are federally regulated, not universally banned. State law may still prohibit them.
• Magazine limits, assault-weapon definitions, and grandfather provisions vary by state.
• Some bans apply to people rather than firearm models. A firearm’s legality can depend on the possessor’s status.

For primary-source information, readers can consult the ATF Firearms Division, the federal statutes in Title 18 of the U.S. Code, and the relevant state legislature or law-enforcement agency. Those sources help distinguish a nationwide prohibition from a state-specific rule or a federal registration requirement.