The National Firearms Act: Regulated Items, Transfers, and Penalties

The National Firearms Act is the 1934 federal law that regulates a specific list of weapons — machine guns, short-barreled rifles, short-barreled shotguns, suppressors, destructive devices, and a catch-all category called “any other weapon” — by requiring every one of them to be registered in a federal database, tied to a specific owner, and cleared through a background check before it changes hands. It sits in the tax code (26 U.S.C. Chapter 53) rather than the criminal code, and for most of its history it imposed a $200 tax on every transfer or manufacture. A July 2025 amendment dropped that tax to $0 for most covered items starting with the January 1, 2026 quarter, but every registration, fingerprint, and background-check requirement remains in force.

What the NFA Regulates

The Act applies to six categories of items defined in 26 U.S.C. § 5845. Possessing something that meets one of these definitions without registering it is a federal felony whether or not you knew it qualified, so the technical thresholds matter.

Machine Guns

Any weapon that fires more than one round with a single pull of the trigger. The definition also reaches the frame or receiver of such a weapon, any part designed exclusively to convert a semi-automatic into a fully automatic, and weapons that have been disabled but can be “readily restored” to automatic fire.¹ Civilian access to machine guns is further limited by the 1986 freeze discussed below.

Short-Barreled Rifles

A rifle with a barrel under 16 inches, or an overall length under 26 inches.¹ This covers both factory-built short rifles and standard rifles someone has cut down.

Short-Barreled Shotguns

A smoothbore shotgun with a barrel under 18 inches, or an overall length under 26 inches.¹ Note the barrel threshold: 16 inches for rifles, 18 inches for shotguns. People confuse the two.

Suppressors

Any device designed to muffle the report of a portable firearm. The definition covers not just a finished suppressor but any part intended for assembling or fabricating one.² Suppressors are the item most affected by the 2025 tax change, since each transfer previously carried the full $200.

Destructive Devices

Two groups. Explosive and incendiary munitions — bombs, grenades, mines, rockets with a propellant charge over four ounces, missiles with an explosive or incendiary charge over a quarter ounce. And any weapon with a bore diameter greater than half an inch, apart from shotguns the ATF has found “particularly suitable for sporting purposes.”² Destructive devices still carry the $200 tax.

Any Other Weapon

Concealable firing devices that don’t fit the standard categories: cane guns, pen guns, wallet holsters that let you fire without drawing, smoothbore pistols designed for shotgun shells.² Conventional rifled pistols and revolvers, and any firearm designed to fire from the shoulder, are excluded. Transfers of an “any other weapon” carried a reduced $5 tax before the 2025 amendment; the tax is now $0.

The 2025 Tax Change

For nearly ninety years the transfer and making tax stayed frozen at the 1934 level of $200 (with the $5 exception for “any other weapon”). Public Law 119-21, signed July 4, 2025, rewrote the rate schedule.³ The current rates are:

Machine guns and destructive devices: $200 per transfer or manufacture.
All other NFA firearms: $0 per transfer or manufacture.⁴

The amendment took effect for calendar quarters beginning more than 90 days after enactment, which made January 1, 2026 the first qualifying quarter. If you’re registering a suppressor, short-barreled rifle, short-barreled shotgun, or an “any other weapon” today, the federal tax is zero. Everything else about the process — the application, the fingerprints, the photograph, the background check, the registration entry — still applies exactly as before.

Registering or Transferring an NFA Item

Every NFA item lawfully held by a civilian is entered in the National Firearms Registration and Transfer Record (NFRTR), the ATF-maintained federal database that tracks each item to a specific individual, corporation, or trust.⁵ No comparable federal registry exists for ordinary firearms.

Two forms handle most civilian transactions. ATF Form 1 is for making an NFA firearm yourself, such as assembling a suppressor from a kit or converting a rifle to a short-barreled configuration.⁶ ATF Form 4 is for buying or receiving an existing NFA item from a dealer or another person.⁷ You have to submit the form and wait for approval before taking possession or beginning work. Building or receiving the item first is a federal crime.

Every application includes two fingerprint cards and a recent photograph for each applicant or responsible person, plus a background check to confirm the applicant is not a prohibited possessor.⁸ Where a tax still applies (machine guns and destructive devices), payment goes in with the form.

Trusts

Many owners register through a firearms trust rather than as an individual. A trust lets more than one person legally possess the same item and simplifies inheritance, since the item passes to a successor trustee without probate. Under ATF Rule 41F, every “responsible person” in the trust — anyone with authority to possess or direct disposition of the firearm — must submit their own fingerprints, photograph, and background-check paperwork, and must send a completed ATF Form 5320.23 to the chief law enforcement officer where they live.⁹ The CLEO doesn’t sign off, but must be notified.

Processing Times

ATF publishes rolling averages for electronic applications. As of March 2026:

Form 4, individual: 6 days.
Form 4, trust: 25 days.
Form 1: 49 days.
Form 5 (tax-exempt transfer): 1 day.¹⁰

Those are averages, and individual files may run longer. Electronic filing brought these numbers down sharply from the paper-era waits that often stretched past a year.

The 1986 Machine Gun Freeze

Machine guns are on the NFA list but sit in a category of their own because of a 1986 amendment. The Firearm Owners Protection Act added 18 U.S.C. § 922(o), which makes it unlawful to transfer or possess a machine gun manufactured or registered after May 19, 1986.¹¹ The narrow exception preserved lawful possession of machine guns already lawfully held before that date.

The result is a fixed supply. Roughly 175,000 transferable machine guns registered before the cutoff are the entire civilian pool, and it shrinks whenever one is destroyed. Prices reflect that scarcity: guns that traded for a few hundred dollars in the mid-1980s now routinely sell for $25,000 to $50,000 or more, which makes the $200 tax a rounding error against the purchase price. Federal firearms licensees who pay the Special Occupational Tax can hold post-1986 machine guns as dealer or law-enforcement samples, but those weapons cannot move to a private individual.

Traveling Across State Lines

Under 18 U.S.C. § 922(a)(4), anyone other than a licensed dealer, manufacturer, or importer needs advance written ATF approval to transport a machine gun, short-barreled rifle, short-barreled shotgun, or destructive device across a state line.¹¹ The request goes on ATF Form 5320.20, and approval covers only the dates you asked for.¹² If your trip runs long, file again.

Suppressors and “any other weapon” items are not on the pre-approval list, so federal law lets you cross state lines with them without a Form 5320.20. State law still controls at the destination. If a common carrier moves the item, the carrier gets a copy of the approved form for the shipment.

Penalties

Section 5861 of Title 26 lists a dozen prohibited acts. The ones that most often catch private owners are possessing an NFA firearm not registered to you, receiving one transferred in violation of the Act, and moving an unregistered NFA firearm across state lines.¹³ Altering or obliterating the serial number is a separate offense.

Any violation of Chapter 53 carries a fine of up to $10,000, up to ten years in prison, or both, and courts may order forfeiture of the item.¹⁴ Because these are felonies, a conviction permanently bars you from possessing any firearm under federal law, not just NFA items. Status is binary. Either the item is registered to you in the NFRTR, or possessing it is a crime. There is no grace period, no good-faith defense, and no way to register an item after the fact if it was never entered in the database.

State Law Still Applies

An approved ATF form does not preempt state law. Eight states prohibit civilian suppressor ownership regardless of federal registration, and some states restrict short-barreled rifles and shotguns or ban civilian machine gun possession outright. Confirm your state permits the specific category before you file anything with ATF, because federal approval on an item your state forbids leaves you in possession of contraband under state law.

1
Bureau of Alcohol, Tobacco, Firearms and Explosives. National Firearms Act – Section: 2.1 Types of NFA Firearms
2
Office of the Law Revision Counsel. 26 U.S.C. 5845 – Definitions
3
Congress.gov. Public Law 119-21
4
Office of the Law Revision Counsel. 26 U.S.C. 5811 – Transfer Tax
5
Office of the Law Revision Counsel. 26 U.S.C. Chapter 53 – Machine Guns, Destructive Devices, and Certain Other Firearms
6
Bureau of Alcohol, Tobacco, Firearms and Explosives. NFA Handbook – Chapter 6: Making NFA Firearms by Nonlicensee
7
Bureau of Alcohol, Tobacco, Firearms and Explosives. NFA Handbook – Chapter 9: Transfers of NFA Firearms
8
Bureau of Alcohol, Tobacco, Firearms and Explosives. NFA Form 1 Submission External Guidance
9
Bureau of Alcohol, Tobacco, Firearms and Explosives. Background Checks for Responsible Persons (Final Rule 41F)
10
Bureau of Alcohol, Tobacco, Firearms and Explosives. Current Processing Times
11
Office of the Law Revision Counsel. 18 U.S.C. 922 – Unlawful Acts
12
Bureau of Alcohol, Tobacco, Firearms and Explosives. Application to Transport Interstate or to Temporarily Export Certain NFA Firearms (ATF Form 5320.20)
13
Office of the Law Revision Counsel. 26 U.S.C. 5861 – Prohibited Acts
14
Office of the Law Revision Counsel. 26 U.S.C. 5871 – Penalties