NFA Items: Suppressors, SBRs, and Tax Stamps Explained
Title II weapons — suppressors, short-barreled rifles, machine guns, AOWs. Buying one means a $200 federal tax stamp, ATF Form 4, fingerprints, a background investigation, and a wait measured in months. Here is what the process actually looks like.
What the NFA regulates
The National Firearms Act of 1934 was the federal government's response to Prohibition-era gang violence. It created a registration and tax scheme — an effective prohibition by paperwork — for categories of firearms Congress considered especially dangerous: machine guns, silencers, sawed-off rifles and shotguns, and "any other weapons" disguised as something else. The 1968 Gun Control Act and the Firearm Owners Protection Act of 1986 updated the scheme, most notably closing the machine gun registry to new civilian manufacture after May 19, 1986.
The NFA doesn't ban these items for civilians — it regulates them. A law-abiding person can buy a suppressor, an SBR, or a transferable pre-1986 machine gun, as long as they pay the tax, pass a federal background investigation, and comply with state law.
The six NFA categories
| Category | What it is | Tax |
|---|---|---|
| Suppressor | Any device for silencing, muffling, or diminishing the report of a firearm. Also called "silencers" in statute. | $200 |
| SBR | Short-barreled rifle. A rifle with a barrel under 16", or an overall length under 26". | $200 |
| SBS | Short-barreled shotgun. A shotgun with a barrel under 18", or an overall length under 26". | $200 |
| Machine gun | Any weapon that fires more than one round per trigger function. Civilian ownership restricted to pre-May 19, 1986 registered transferables. | $200 |
| Destructive device | Explosives over 1/4 lb, grenades, firearms with bore over 0.5" not deemed "sporting" (with specific exceptions). | $200 |
| AOW | Any other weapon. Concealable weapons that fire a projectile but don't fit neatly into "pistol" or "rifle" — pen guns, cane guns, smooth-bore pistols, some pistol-gripped-only shotguns. | $5 |
The $5 AOW tax is only for transfers. Making an AOW still carries the $200 manufacture tax. This is why AOW conversions are a niche corner of the NFA world rather than a mass market.
The $200 tax stamp
The "tax stamp" is literally that — a stamp the ATF affixes to an approved transfer form, evidencing that the $200 excise tax under 26 U.S.C. §5811 has been paid. The tax was set at $200 in 1934. Congress has never adjusted it for inflation; $200 in 1934 is roughly equivalent to $4,800 today. That flat nominal rate is the only reason the modern civilian suppressor market exists.
The stamp is per item, per transfer. If you buy a suppressor, your wife later inherits it, and she later sells it to a friend, that's three taxed transfers — although intra-family transfers can often use a tax-free Form 5 if they occur upon death (estate transfer).
Form 4: buying an NFA item step by step
1. Pick your item and dealer
Not every FFL handles NFA. You need a dealer with a Special Occupational Tax (SOT) Class 3 designation. LocalFFL tags NFA-qualified dealers on their profile pages — look for the "NFA" tag. Many dealers partner with NFA-specialist retailers (Silencer Shop, Capitol Armory) who handle the paperwork and ship to your local Class 3 on approval.
2. Decide: individual or trust
See trust vs. individual. For a first purchase, most buyers go individual unless they want co-possession by family members.
3. Dealer initiates Form 4
The dealer files ATF Form 4 (Application for Tax Paid Transfer and Registration of Firearm), either via eForms (strongly recommended) or on paper. You provide:
- Two passport-style photos (eForm uploads them)
- Fingerprint cards (FD-258) — two sets for paper, digital for eForms
- Chief Law Enforcement Officer (CLEO) notification — your local sheriff or chief gets a copy. They don't approve, just get notice. (Note: the pre-2016 CLEO signoff requirement was replaced with notification by ATF Rule 41F.)
4. Pay the tax
$200 to the ATF (or $5 for AOW). Paid by credit card during eForm submission or by check on paper. The dealer separately charges you for the item itself and any transfer fees.
5. Wait
See wait times. You cannot take possession, install the suppressor, or configure the SBR until the approved Form 4 is returned.
6. Pickup
Once approved, the dealer gets a digital or paper stamp. You go in, sign Form 4473 (yes, a 4473 for an NFA item — the 4473 is still required because it's a firearm transfer), and take the item home. Keep a copy of the approved Form 4 with the item permanently. If ATF agents ask to see it, they're asking lawfully and you should produce it.
Trust vs. individual
Individual
Simplest path. You are the sole registered owner. Only you can possess the item. If someone else handles it in your presence, federal law requires your direct, physical supervision — you must be in the room and in control.
Trust
A gun trust is a revocable living trust that owns the NFA item. Co-trustees (spouse, adult children, shooting partners) can possess the item without you being present. Upon your death, the trust passes according to its terms without going through probate — and without the $200 transfer tax, via Form 5.
Trade-offs since ATF Rule 41F (2016):
- Every "responsible person" on the trust submits fingerprints and photos at application.
- The CLEO notification requirement extended to trusts as well, eliminating the pre-41F advantage of avoiding CLEO involvement.
- Trust submissions historically take longer to process than individual ones (more people to check).
A properly drafted NFA trust costs $100–$400 through an attorney or a specialized service. Generic "silencer trusts" offered free by dealers work, but are often boilerplate and may not serve your estate planning well. If the NFA collection is meaningful, pay for a real trust.
Current wait times
ATF Form 4 processing times have varied dramatically over the last decade — from over 12 months in 2017 to under 90 days during the 2023–2024 eForm 4 rollout for individuals. Current times fluctuate. Check the ATF's published NFA processing times before you submit.
What affects your wait
- eForm vs. paper. eForm 4 is faster — sometimes dramatically — than paper.
- Individual vs. trust. Individuals typically clear faster because there's only one responsible person to check.
- Workload. ATF workload spikes after industry price drops and promotions. Silencer Shop and similar bulk submitters can extend queue times when they dump thousands of applications.
- Prior contacts. A name match with a prior NFA transaction — which is actually good — can accelerate the examiner's decision.
State-law prohibitions
Federal approval is necessary but not sufficient. States can and do prohibit specific NFA categories outright. Before you file Form 4, confirm that the item is legal to possess in your state.
States where suppressors remain restricted or prohibited
The overwhelming majority of states allow civilian ownership of suppressors. A small handful have carve-outs or outright bans. Check your state page on LocalFFL for a current summary, and confirm with your dealer. Note that "suppressors are legal" under state law doesn't always mean they can be used for hunting — some states restrict hunting with a suppressor even where ownership is fine.
SBR and machine gun prohibitions
SBRs are prohibited in some states (California, New Jersey), restricted to specific permit holders in others, and legal with federal approval in most. Machine guns are more restrictive still — transferable pre-1986 registered machine guns are legal federally, but banned in states including California, Hawaii, Illinois, Iowa, Kansas (certain categories), Minnesota, New Jersey, New York, Rhode Island, and Washington. Verify current state law.
Traveling with NFA items
Suppressors
Interstate travel with a registered suppressor is not restricted by federal law — you can cross state lines freely, provided the item is legal in your destination. Most owners still carry a copy of the approved Form 4.
SBRs, SBSs, machine guns, destructive devices
These require prior ATF approval to cross state lines. File ATF Form 5320.20 (Application to Transport Interstate or to Temporarily Export Certain NFA Firearms) at least 30 days before your trip. Approval is typically routine for lawful purposes (competitions, hunting trips where the item is legal at destination). Approval is per-trip or time-bounded, depending on how you fill the form.
Frequently asked questions
Can I shoot my suppressor while I'm waiting for approval?
No. Until the ATF approves and returns the Form 4, the suppressor is the dealer's property. Touching it constitutes constructive possession. The dealer can let you look, not shoot.
What if I want to sell my NFA item later?
The buyer submits their own Form 4, pays their own $200, and waits. You keep possession until their approval comes back. Tax-paid transfers are non-refundable, so there's no recovery of the original $200.
Can a convicted felon own an NFA item?
No. All federal prohibited-person categories under 18 U.S.C. §922(g) apply. An NFA purchase involves both a 4473 and a Form 4 background investigation — the scrutiny is considerably higher than a standard firearm purchase.
Do I need a permit from my sheriff?
No. Since ATF Rule 41F (2016), CLEO approval is no longer required. CLEO notification — a copy of the application sent to your local chief law enforcement officer — is now the standard. They cannot block the transfer.
Are "solvent trap" kits legal?
Solvent traps as sold are legal accessories. Using or modifying them as suppressors is illegal possession of an unregistered NFA item — a 10-year federal felony. The ATF has prosecuted solvent-trap cases actively over the last several years. Don't.