An SOT, or Special Occupational Taxpayer, is a federal firearms licensee that pays an annual special tax to do business in National Firearms Act items: suppressors, short-barrel rifles, short-barrel shotguns, machine guns, and other NFA-regulated firearms. The SOT is not a separate license. It is a tax status you add on top of an existing FFL, and the class you register under (1, 2, or 3) has to match what your FFL type already allows you to do.
If customers keep asking your shop about suppressors, you have probably asked yourself whether becoming an SOT is worth it. This guide covers what each SOT class is, which FFL types pair with each class, what it costs, and how registration actually works.
SOT Is a Tax Status, Not a License
The Federal Firearms License authorizes your business to deal, manufacture, or import firearms. The National Firearms Act of 1934 regulates a special category of items on top of that, and it funds its own enforcement with a special occupational tax. Registering as a Special Occupational Taxpayer means paying that tax so your existing FFL can also handle NFA items.
Two practical consequences follow from that:
- You must hold an FFL first. There is no standalone SOT. You add the SOT to a live license, and the SOT class must be consistent with your FFL license type.
- The SOT covers the license, not the person. One registration covers your premises and your employees working under the license, but each licensed location needs its own SOT registration.
The Three SOT Classes
Class 1: Importer of NFA Firearms
A Class 1 SOT pairs with an importer FFL (Type 08 or Type 11) and authorizes importing NFA items into the United States. Import approvals run through ATF Form 6, and imports of machine guns and certain other items are limited to government, law enforcement, and dealer-sales-sample channels. Unless importing is your core business, this is not the class you are looking for.
Class 2: Manufacturer of NFA Firearms
A Class 2 SOT pairs with a manufacturer FFL (Type 07 or Type 10) and authorizes making NFA firearms: manufacturing suppressors, building short-barrel rifles, and making post-1986 machine guns as sales samples for law enforcement demonstration. A Class 2 SOT can also deal in NFA items without paying a second tax, which is why many gun stores that do gunsmithing and custom builds go Type 07 FFL plus Class 2 SOT instead of Type 01 plus Class 3. The manufacturing authority comes with additional obligations, including ITAR/AECA registration questions and excise tax on manufactured firearms, so the extra flexibility is not free.
Class 3: Dealer in NFA Firearms
A Class 3 SOT pairs with a dealer FFL (Type 01 or Type 02) and authorizes buying and selling NFA items at retail. This is the class behind the common shorthand "Class 3 dealer," and it is the right fit for the typical gun store that wants to add suppressors and short-barrel rifles to the counter. Note the shorthand runs backward in casual conversation: there is no such thing as a "Class 3 license," and the items themselves are NFA firearms, not "Class 3 firearms." The class number describes your tax status only.
Which FFL Types Pair With Which SOT Class
| SOT Class | What it authorizes | Compatible FFL types | Typical business |
|---|---|---|---|
| Class 1 | Import NFA firearms | Type 08, Type 11 | Importers |
| Class 2 | Manufacture (and deal in) NFA firearms | Type 07, Type 10 | Manufacturers, custom builders, stores that also make suppressors or SBRs |
| Class 3 | Deal in NFA firearms | Type 01, Type 02 | Retail gun stores, pawnbrokers with a Type 02 |
A Type 03 collector's license and a Type 06 ammunition manufacturer cannot take an SOT. If you are still deciding which license fits your business model, start with our breakdown of all nine FFL license types and work forward from there.
What an SOT Costs
- $500 per year for Class 3 dealers, and for Class 1 or Class 2 businesses with gross receipts under $500,000 in the prior tax year (the reduced rate).
- $1,000 per year for Class 1 and Class 2 businesses above that threshold.
The tax year runs July 1 through June 30, and the full annual tax is due no matter when you register. Register in May and you owe the full amount for a tax year that ends weeks later, so most new SOTs time their first registration to early July. There is no proration and no refund for an unused portion of the year.
How to Register as an SOT
- Hold the right FFL. Confirm your license type supports the class you want, or upgrade your FFL first.
- File ATF Form 5630.7. The Special Tax Registration and Return, with payment, to the ATF's tax processing center. Your registration takes effect when the ATF receives the form and payment, not when approval paperwork comes back.
- Receive your special tax stamp. Keep it available for inspection at the licensed premises.
- Renew every year. The ATF mails renewal packages before July 1. A lapsed SOT means every NFA item in your inventory is suddenly sitting with a business that is no longer qualified to hold it for sale, which is an expensive paperwork problem to unwind.
What Changes Operationally Once You Are an SOT
The tax is the easy part. The operational load is the real decision:
- Transfers run on NFA forms with real wait times. Retail sales to individuals move on ATF Form 4 with a $200 transfer tax per item ($5 for AOWs) and approval measured in months, though eForms has shortened it substantially. Dealer-to-dealer transfers move tax-free on Form 3. Your customers wait for approval before they can take possession, which changes how you sell, store, and follow up.
- Inventory sits longer and must be tracked harder. A suppressor can live in your safe for months between sale and approved transfer. Your NFA recordkeeping has to show exactly where every serialized item stands: in inventory, pending on a Form 4, or transferred out on an approved form.
- Your A&D book and 4473 discipline matter more, not less. NFA transfers still complete with a Form 4473 at handover, layered on top of the approved NFA form, and in most cases a NICS check as well (some states treat the approved ATF form or a state permit as a Brady exemption, so verify your state’s rules). ATF inspections of SOT dealers walk both sets of records against each other.
- State law still applies. Several states prohibit or restrict suppressors, SBRs, or machine gun sales regardless of your federal status. Verify your state before you invest in inventory.
For the typical gun store, the math is straightforward: suppressor demand keeps growing, margins on NFA items are healthy, and a $500 annual tax pays for itself with a handful of sales. The stores that struggle with SOT status are the ones that treat NFA tracking as a side spreadsheet instead of running it through the same point of sale and compliance system as the rest of the counter.