What Is the National Firearms Act? NFA Explained (2026)

Last updated March 2026 · By Nick Hall, firearm owner who has completed multiple NFA Form 4 tax stamp transfers

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Disclaimer: This article is for general informational purposes only and does not constitute legal advice. Firearms laws are complex and change frequently. Always consult a qualified attorney or your local ATF field office for guidance specific to your situation.

What Is the National Firearms Act?

The National Firearms Act is the reason you can’t just walk into a gun store and buy a suppressor like you’d buy a box of 9mm. It’s the reason your buddy’s AR “pistol” with a brace exists. It’s the reason transferable machine guns cost more than a new truck. And it’s the single most misunderstood piece of firearms legislation in America.

Passed in 1934, the NFA doesn’t actually ban anything outright. Instead, it creates a federal registry for certain categories of firearms and slaps a $200 tax on every transfer. That’s the “tax stamp” you’ve heard people talk about. You pay the government $200, submit a mountain of paperwork, wait an absurd amount of time, and then you can pick up your suppressor or short-barreled rifle. Simple in theory. Agonizing in practice. Three federal lawsuits are now challenging the registry’s constitutional foundation after the One Big Beautiful Bill zeroed the underlying transfer and making tax.

I’ve been through the NFA process multiple times, and I can tell you firsthand: it tests your patience like nothing else in the firearms world. But understanding how it works, what it covers, and how to actually get through the process without losing your mind is something every serious gun owner should know. So let’s break it down.

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Why the NFA Exists (Blame Prohibition)

The 1920s and early 1930s were basically a live-action gangster movie. Al Capone’s guys were spraying Thompson submachine guns in the streets of Chicago. Bonnie and Clyde were cutting down Browning Automatic Rifles (stolen from National Guard armories, by the way) and sawing off shotgun barrels. John Dillinger, Pretty Boy Floyd, Baby Face Nelson. These people were national news, and the public was terrified.

Congress responded the way Congress does: they passed a law. The National Firearms Act of 1934 didn’t ban machine guns or sawed-off shotguns. Instead, it made them expensive and bureaucratically painful to acquire through registration and a $200 tax. In 1934 dollars, that $200 was roughly equivalent to $4,500 today. That was the whole point. Price the criminals out.

Did it work? Depends who you ask. The gangster era ended, but that had more to do with Prohibition ending than any tax stamp. What the NFA definitely did was create a bureaucratic framework that still governs these items 90 years later. The $200 tax hasn’t changed since 1934. Not once. Adjusted for inflation it’s basically nothing now, but the wait times and paperwork? Those have only gotten worse. For the full historical context on how firearms evolved alongside these laws, check out our history of firearms guide.

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The Six NFA Categories (What’s Actually Regulated)

The NFA regulates six specific categories of weapons. Possessing any of these without a valid tax stamp and registration is a federal felony. We’re talking 10 years in prison and $250,000 in fines. The ATF does not mess around here. Not even a little.

1. Machine Guns

Any firearm that fires more than one round per single pull of the trigger. Full auto, burst fire, doesn’t matter. If you pull the trigger once and more than one bullet comes out, that’s a machine gun under federal law. The legal definition also covers the parts that make it happen: auto sears, drop-in auto sears (DIAS), lightning links, and conversion kits. Having the part alone, even uninstalled, can be enough for a conviction.

I’ll get into the Hughes Amendment below, because that’s the real gut punch for anyone interested in full-auto firearms. Spoiler: civilian machine gun ownership is technically legal, but your wallet is going to hate you.

2. Short-Barreled Rifles (SBRs)

A rifle with a barrel under 16 inches, or an overall length under 26 inches. This is the category that drives the most NFA registrations right now, and it’s the reason the entire pistol brace saga happened.

Here’s the deal. Military M4 carbines run 14.5-inch barrels. The civilian AR-15s you see everywhere have 16-inch barrels specifically to avoid NFA classification. That extra inch and a half? That’s purely a legal requirement. If you want a 10.5-inch or 11.5-inch barrel on your AR (which a lot of people do for home defense or truck guns), you’ve got two options: register it as an SBR with a tax stamp, or build it as a “pistol” with a pistol brace instead of a stock.

The pistol brace workaround was the most popular route for years. The ATF’s back-and-forth on brace legality has been one of the messiest regulatory situations in recent firearms history. If you’re running a braced pistol, stay current on the rules because they’ve changed multiple times.

3. Short-Barreled Shotguns (SBSs)

Same concept as SBRs but for shotguns. Barrel under 18 inches or overall length under 26 inches makes it an NFA item. This is why your pump-action shotgun or semi-auto tactical shotgun has an 18-inch barrel as the shortest factory option.

SBSs are less common in the NFA world than SBRs or suppressors, mostly because there aren’t as many compelling use cases. A 14-inch shotgun barrel is cool, sure. But the difference between 14 and 18 inches on a shotgun isn’t as tactically significant as the difference between a 10.5-inch and 16-inch AR barrel. Still, if you want to chop a Mossberg 590 or build a short Remington 870, you’ll need that stamp.

4. Suppressors (Silencers)

This is the NFA category that genuinely makes me angry about the law. Suppressors are hearing protection devices. Period. They don’t make guns “silent” like in the movies. A suppressed 9mm pistol still registers around 130-135 decibels. That’s louder than a rock concert. A suppressed .308 rifle is even louder. What suppressors do is bring the sound down from “instant permanent hearing damage” (160+ dB) to “still very loud but your ears might survive without doubling up on ear pro.”

In most of Europe, suppressors are either unregulated or actively encouraged. You can buy one off the shelf in many countries. In New Zealand, they’ll sell you a suppressor at the hardware store. Meanwhile, in America, you get to pay $200 and wait months for what is essentially a safety device. In 42 states, suppressors are legal with an NFA stamp. They’re banned entirely in California, New York, New Jersey, Massachusetts, Hawaii, Illinois, Delaware, and Rhode Island.

If you shoot regularly, especially outdoors or while hunting, a suppressor is one of the best investments you can make for your long-term hearing health. The NFA process is annoying, but the end result is worth it. I run cans on almost everything I shoot now, and I genuinely wish I’d started sooner.

5. Destructive Devices

This one covers two things. First: explosive ordnance. Grenades, mines, rockets, bombs. Yes, you can technically own these with NFA registration, though finding someone who’ll sell you a live grenade is a different conversation entirely.

Second: any firearm with a bore diameter over half an inch (0.50 caliber), with exceptions carved out for shotguns and firearms the ATF deems to have a “sporting purpose.” This is why .50 BMG rifles are not destructive devices. The .50 BMG cartridge has a bore of exactly 0.50 inches, which falls right at the threshold. Anything bigger, like a 20mm anti-tank rifle or a 40mm grenade launcher, falls into destructive device territory. Check out our 50 BMG buyer’s guide if you’re curious about the biggest stuff you can own without the DD classification.

6. Any Other Weapon (AOW)

The NFA’s catch-all category for weird stuff that doesn’t fit anywhere else. Pen guns. Cane guns. Wallet holsters that allow firing without removing the pistol. Smooth-bore pistols. If it’s a weapon and it’s strange enough to not fit the other five categories, it probably lands here.

The one nice thing about AOWs: the transfer tax is only $5 instead of $200. Manufacturing one still costs $200 on a Form 1, but if you’re buying an existing AOW from a dealer, it’s a $5 stamp. That’s the cheapest entry point into NFA ownership, if you can find an AOW you actually want.

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The Hughes Amendment: Why Machine Guns Cost More Than a Car

This is where NFA law goes from “annoying but manageable” to “genuinely absurd.” The Firearm Owners Protection Act of 1986 (FOPA) was generally a pro-gun bill. It rolled back some of the worst excesses of the ATF, protected interstate firearms transportation, and limited the ATF’s ability to inspect dealers. Good stuff, mostly.

Then Representative William Hughes slipped in an amendment at the last minute that banned the manufacture and registration of new machine guns for civilian ownership after May 19, 1986. It passed in a controversial voice vote that many witnesses say was improperly counted. The bill’s sponsor, Senator James McClure, reportedly wanted to strip the amendment but couldn’t without killing the entire bill. So it stayed.

The result: the supply of transferable machine guns was frozen in 1986. No new ones will ever enter the civilian market. Basic economics takes over from there. A transferable M16 lower receiver that might have cost $1,000 in 1986 now sells for $30,000 to $50,000. A registered drop-in auto sear (RDIAS) runs $30,000 and up. A transferable Thompson submachine gun? $25,000 to $40,000, depending on variant and condition. Want something exotic like an MP5 or an Uzi? Even more. For a deep dive on the Thompson specifically, see our guide to buying a Tommy Gun.

These aren’t range toys anymore. They’re investments. Many transferable machine guns have appreciated faster than the stock market over the last 40 years. The people who bought them in the ’90s for $5,000-$10,000 are sitting on six-figure assets. Good for them. Terrible for everyone else who’d like to legally experience full auto without taking out a second mortgage.

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Form 1 vs. Form 4: The Two Ways to Get NFA Items

There are two ATF forms that civilians primarily deal with in the NFA world, and people confuse them constantly. Here’s the difference.

Form 1: Making an NFA Item

ATF Form 1 (Application to Make and Register a Firearm) is what you file when you’re creating an NFA item yourself. The most common example: you have an AR-15 pistol lower and you want to put a stock on it, making it an SBR. You file the Form 1, pay $200, wait for approval, and then you can legally install the stock and/or short barrel.

Form 1s used to be faster than Form 4s because they were submitted electronically (eForms) while Form 4s were still paper-only. That advantage has mostly evaporated now that eForm 4s exist. As of early 2026, eForm 1 approvals are running anywhere from a few weeks to a few months, depending on ATF workload and whether they decide to send your prints to the FBI for additional review.

One thing worth knowing before you file: the information on a Form 1 is supposed to be confidential under 26 U.S.C. § 6103, but the recent GOA complaint over ATF Form 1 disclosures on a public docket shows that the system can fail in unhappy ways. Worth keeping an eye on if you have an active Form 1 in process or any active litigation that touches the ATF.

Form 4: Buying an Existing NFA Item

ATF Form 4 (Application for Tax Paid Transfer and Registration) is what you file when you’re buying an existing NFA item from a dealer. This is the form for suppressors, transferable machine guns, and anything else you’re purchasing rather than making yourself.

The eForm 4 process was a game changer when it launched in early 2022. Before that, paper Form 4s were regularly taking 9 to 14 months. I waited 11 months for one of my first suppressors on paper. It was brutal. You pay for the item, it sits in your dealer’s safe, and you just… wait. Every month you check, and every month the answer is the same: “pending.”

eForm 4s brought wait times down dramatically at first, with some approvals coming through in under 90 days. As of 2026, the typical eForm 4 wait is running 4 to 8 months, though some people report faster or slower depending on their region and individual circumstances. Still better than the paper era. If your dealer isn’t using eForms by now, find a new dealer.

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The NFA Purchase Process: Step by Step

Alright, let’s walk through what actually happens when you buy an NFA item. I’ll use a suppressor as the example since that’s what most people start with.

Step 1: Find and buy the suppressor. You purchase it from a Class 3 dealer (technically a dealer with a Special Occupational Tax, or SOT). Many online retailers sell NFA items and will ship them to a local SOT dealer for transfer. You pay the full price of the suppressor up front. Yes, you pay for something you can’t take home yet. Welcome to the NFA.

Step 2: Fill out the ATF Form 4. Your dealer will walk you through this, and most use the eForm system now. You’ll need a passport-style photo (2×2 inches) and two sets of fingerprint cards. If you’ve never been fingerprinted before, your local police station, UPS Store, or even some gun shops will do it for a small fee.

Step 3: Pay the $200 tax. This is paid to the ATF during the Form 4 submission. It’s per item, not per year. Once you pay it, that item is registered to you forever (or until you transfer it to someone else, at which point they pay the $200).

Step 4: CLEO notification. A copy of your Form 4 gets sent to your local Chief Law Enforcement Officer (sheriff or police chief). This is a notification, not a permission request. They can’t deny your transfer. They just get told it’s happening. Before 2016, you needed actual CLEO sign-off, which meant some sheriffs could (and did) block NFA transfers in their jurisdiction. ATF Rule 41F changed that to notification-only.

Step 5: Wait. Then wait some more. This is the worst part. Your suppressor sits in your dealer’s safe while the ATF processes your form. You’ll get an “approved” notification eventually, and your dealer will receive the stamp. As of 2026, eForm 4 wait times are typically 4 to 8 months. Some guys get lucky with 90-day approvals. Some wait nearly a year. There’s no real rhyme or reason to it.

Step 6: Pick up your suppressor. Once approved, you do a standard 4473 (the same form you fill out for any gun purchase), pass your NICS background check, and walk out the door with your new can. Finally.

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NFA Trusts: Why Most Experienced Buyers Use Them

You can file NFA paperwork as an individual or through a legal entity, and the most popular entity is a gun trust (sometimes called an NFA trust). I’d recommend a trust for almost everyone, and here’s why.

When you register an NFA item as an individual, only you can legally possess it. Your spouse can’t take it to the range without you. Your buddy can’t borrow your suppressor. If you die, your family has to navigate an NFA transfer process during probate, which can be a nightmare when emotions are already running high.

A gun trust solves all of that. You create a trust, name “responsible persons” (your spouse, adult children, trusted friends), and register your NFA items to the trust. Any responsible person on the trust can legally possess the items. Estate planning is built in because the trust itself survives you. If something happens, the successor trustee takes over without any ATF transfer required.

The downside: every responsible person on the trust has to submit photos and fingerprints with each Form 4. If you’ve got five people on your trust, that’s five sets of fingerprints and five photos every time you buy a new suppressor. Some people keep their trust lean (just themselves and a spouse) for this reason. Others don’t mind the extra paperwork.

Setting up a gun trust costs anywhere from $30 for a basic online template to $300+ for one drafted by a firearms attorney. If you’re planning to own multiple NFA items (and most people who buy one end up buying several), spend the money on a proper trust. It’s worth it.

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State-Level NFA Restrictions

Federal law is just the floor. Your state can absolutely ban NFA items that are legal under federal law, and several do. Here’s the rough breakdown.

Suppressors: Legal in 42 states. Banned in California, New York, New Jersey, Massachusetts, Hawaii, Illinois, Delaware, and Rhode Island. If you live in one of those eight states, you’re out of luck. There’s no workaround.

SBRs: Legal in most states, but banned or heavily restricted in New York, New Jersey, California, and a handful of others. Some states that ban SBRs still allow AR pistols with braces, which is one reason the brace market exploded.

Machine guns: Even pre-86 transferables are banned for civilian possession in several states, including California, New York, Illinois, and others. If your state bans them, a federal tax stamp won’t save you.

Bottom line: always verify your state’s laws before you start an NFA purchase. Our gun laws by state hub has detailed guides for all 50 states. Don’t assume federal legality means state legality. It doesn’t.

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Common NFA Mistakes That Can Ruin Your Life

I’m not being dramatic with that heading. NFA violations are federal felonies. Ten years in federal prison. Here are the mistakes I see people stumble toward.

Accidentally making an SBR. You put a stock on an AR pistol without a Form 1 approval. Doesn’t matter if you “didn’t know.” Doesn’t matter if it was temporary. You just manufactured an unregistered NFA firearm. This is the most common way regular gun owners accidentally commit federal felonies.

Crossing state lines without notification. If you’re traveling with an NFA item (other than a suppressor or AOW), you need to file an ATF Form 5320.20 to transport it across state lines. Yes, every time. People forget this with SBRs constantly. Suppressors and AOWs are exempt from the interstate notification requirement, which is one more reason suppressors are the easiest NFA entry point.

Letting the wrong person possess your item. If your NFA items are registered to you as an individual, nobody else can have unsupervised possession. Your wife can’t take your suppressor to the range alone. Your friend can’t borrow your SBR for a weekend. This is another big reason to use a trust.

Buying solvent traps with intent. Solvent traps are cleaning devices. Wink wink. The ATF has been aggressively going after solvent trap companies and buyers who clearly intend to convert them into suppressors without a Form 1. Don’t play games here. If you want a suppressor, do the paperwork and buy a real one.

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Is the NFA Process Worth It?

Honestly? Yes. With some caveats.

Suppressors are absolutely worth the wait and the $200. If you shoot with any regularity, a good can transforms the experience. Less noise for your neighbors, less recoil on many platforms, and dramatically better hearing protection. I genuinely believe every centerfire rifle and pistol should have a suppressor option, and the NFA’s treatment of them as equivalent to machine guns is absurd. But that’s the law we’ve got.

SBRs can be worth it depending on your use case. If you want a short AR for home defense and you don’t want to deal with brace legality questions, just stamp it and be done. The peace of mind of knowing you’re 100% legal is worth $200. That said, a lot of people are perfectly happy with 16-inch barrels and pistol configurations.

Machine guns? Unless you’ve got serious disposable income, this is a dream more than a plan for most of us. But if you ever get the chance to shoot one at a range rental or a friend’s, do it. Full auto is an experience everyone should have at least once.

The NFA is 90 years old and it shows. The process is slow, the logic behind some of the classifications is outdated, and the fact that a safety device like a suppressor requires the same paperwork as a machine gun is genuinely ridiculous. But until the law changes, it’s what we’ve got. Learn the rules, follow the process, and eventually you’ll get that approved stamp notification. And it’ll feel like Christmas morning. Trust me.

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• Military vs Civilian Firearms
• Pistol Brace Rules: Latest News
• 7 Best AR Pistol Braces
• 10 Best AR-15 Rifles
• Best Guns for Home Defense
• HK SP5 Review
• Q Honey Badger Review
• Thompson Submachine Gun Guide
• 50 BMG Buyer’s Guide
• 10 Best .50 BMG Rifles
• Special Forces Guns You Can Buy
• The History of Firearms
• Gun Laws by State

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FAQ: National Firearms Act

Frequently Asked Questions