Form 4 Prep Walkthrough: Every Question Explained
A field-by-field guide to the ATF Form 4 (5320.4) for first-time buyers
By StampSwap · Last verified July 2026
This walkthrough is educational and mirrors the actual fields on the ATF Form 4. It is not legal advice. If your situation is complicated, talk to an attorney or your dealer.
In This Guide
- 1. What the Form 4 Is
- 2. How You'll File: Individual, Trust, Corporation, or Entity
- 3. The Firearm Section (Field 4)
- 4. Transfer Tax
- 5. Your CLEO Section (Field 12)
- 6. The Certification Questions (14a–14m)
- 7. Necessity Statement (SBR/SBS Only)
- 8. Personal Details the Form Needs
- 9. What Happens After You Certify
- 10. Glossary
1. What the Form 4 Is
ATF Form 4 — officially “Application for Tax Paid Transfer and Registration of Firearm” (ATF 5320.4) — is the application you submit to legally transfer an NFA item like a suppressor into your name. Nothing changes hands until the ATF approves it. The form asks a lot of questions, and for a first-time buyer that can be intimidating. The goal of this guide is simple: by the time you open the form, no question should surprise you.
When you have an active transaction on StampSwap, the Form 4 Prep Tool inside your transaction dashboard walks you through the same fields you'll see on eForms, one step at a time, and explains what each one is asking. The most sensitive fields — your SSN, date of birth, place of birth, and citizenship details — stay in your browser and are never sent to or stored on our servers. The tool is a preparation and reference aid: you still enter and submit the real application yourself through ATF eForms.
Filing electronically through eForms is the way to go. Current approval times are running about 10-15 days for individuals and 25-30 days for trusts and legal entities — dramatically faster than the paper era. For the full step-by-step transfer process, see our NFA Transfer Process guide.
2. How You'll File: Individual, Trust, Corporation, or Entity
One of the first decisions on the form is the transferee type — who, legally, is taking ownership. The form gives you four choices, and the Prep Tool mirrors them exactly:
Individual
You, personally, own the item. Simplest paperwork, fastest approval, and only you can legally possess it. You'll answer the 14a–14m certification questions yourself.
Trust
An NFA trust owns the item. Anyone named as a trustee can legally possess it, which makes sharing and estate planning easier. The trade-off: every responsible person has extra paperwork (see below), and trust approvals run a little slower.
Corporation
A corporation is the registered owner. Uncommon for personal buyers; mostly used by businesses. Same responsible-person requirements as a trust.
Other Legal Entity
An LLC, partnership, or similar entity. Like a corporation, it's a legal person that owns the item and carries responsible-person requirements.
What is a “responsible person”?
A responsible person is anyone with the authority to possess or direct the disposition of the NFA items held by a trust, corporation, or other entity — typically the settlor and every trustee of a trust, or the officers of a company. If you file as a trust or entity, each responsible person must submit ATF Form 5320.23 along with their own passport-style photo and fingerprints. If you file as an individual, there are no responsible persons other than you, and you skip Form 5320.23 entirely. This is the main reason a straightforward personal purchase is often filed as an individual.
3. The Firearm Section (Field 4)
Field 4 describes the exact item being transferred. Every value here comes from the seller's existing approved tax stamp and the StampSwap listing — not from memory. On StampSwap, the Prep Tool pre-fills what it can from the transaction record so you're confirming values rather than guessing. The fields are:
- •4a. Manufacturer / Maker & address — who made the item (e.g., SilencerCo). Comes from the item's markings and the listing.
- •4b. Type — Silencer, Rifle (SBR), Shotgun (SBS), or Any Other Weapon. For a suppressor, this is “Silencer.”
- •4c. Caliber or gauge — e.g., 9mm, .30 cal.
- •4d. Model — the product model (e.g., Omega 36M).
- •4e. Barrel length — only for SBRs and SBSs. Suppressors have no barrel, so this is N/A.
- •4f. Overall length — the length of the item.
- •4g. Serial number — must match the serial engraved on the item exactly, including spaces and dashes. A wrong serial number is one of the top reasons a Form 4 gets denied. Read it off the item itself, not from memory or an old receipt.
Prior ATF Control Number
This is a number specific to used-item transfers. When the seller acquired the item, the ATF issued them an approved Form 4 with a control number. That number is the Prior ATF Control Number — it ties your new application to the item's existing registration in the NFRTR. You don't make this up; the seller (or the transferring dealer) supplies it from their existing approved Form 4. On a brand-new item bought from a dealer, there may be no prior control number to enter.
4. Transfer Tax
The form asks for the transfer tax amount. Since January 1, 2026, the transfer tax for suppressors, SBRs, SBSs, and AOWs is $0. If you're buying a suppressor on StampSwap, this is your answer.
The form still shows a $200 option because that amount still applies to machine guns and destructive devices — item categories that are not permitted on StampSwap. You will not select $200 for any item you buy here.
Note: Even though the tax is $0, the Form 4 process — background check, fingerprints, photo, and CLEO notification — is still required for every NFA transfer. Read more in The $0 Tax Stamp guide.
5. Your CLEO Section (Field 12)
Field 12 asks for your Chief Law Enforcement Officer (CLEO). Your CLEO is the top local law enforcement official for where you live — usually your county sheriff, your city's chief of police, or in some places the state attorney general. The form collects three things: the agency or department name, the official's name and title, and their mailing address.
The single most important thing to understand: this is a notification, not an approval. Your CLEO cannot deny or block your transfer. You (or eForms) simply send them a copy of the application so they're aware of it. There is no permission to wait for.
How to find the right name and address
For most people, the answer is the county sheriff. Go to your county sheriff's official website, find the sheriff's name and the department's official mailing address (the “Contact” or “About” page), and use those. If you live inside a city with its own police department, the chief of police works too. Use the official government address, not a substation or a P.O. box you found on a random site.
6. The Certification Questions (14a–14m)
Field 14 is a series of yes/no questions the transferee answers. Most of them are “prohibited person” screeners — the same disqualifiers you'd see on a standard Form 4473 when buying a regular gun. For a lawful transfer, the honest answer to nearly all of them is “No”. Here is what each one is actually asking, in plain English:
- 14a. Do you plan to use any firearm on this form to commit a serious crime — a felony, an act of terrorism, or drug trafficking? “Yes” means you intend to use it criminally.
- 14b. Do you plan to transfer the item to a prohibited person (anyone described in 14c–14m who doesn't qualify for an exception)? “Yes” means you intend to hand it off to someone who can't legally have it.
- 14c. Are you currently under indictment or charged with a felony (a crime that could carry more than one year in prison)? “Yes” means charges are pending against you.
- 14d. Have you ever been convicted of a felony — a crime the judge could have imprisoned you for more than a year — even if you got probation or a shorter sentence? “Yes” means a qualifying conviction is on your record.
- 14e. Are you a fugitive from justice — fleeing a state to avoid prosecution or a court order? “Yes” means you're on the run.
- 14f. Are you an unlawful user of, or addicted to, marijuana or any controlled substance? This includes marijuana even where state-legal, because it remains federally controlled. “Yes” means current unlawful use or addiction.
- 14g. Since age 16, have you ever been adjudicated as a mental defective or committed to a mental institution (a formal court/agency ruling or involuntary commitment — not ordinary counseling or voluntary treatment)? “Yes” means such a ruling exists.
- 14h. Were you discharged from the Armed Forces under dishonorable conditions? “Yes” means a dishonorable discharge specifically (not a general or honorable one).
- 14i. Are you subject to a court order that restrains you from harassing, stalking, or threatening an intimate partner or their child? “Yes” means such a restraining order is active against you.
- 14j. Have you ever been convicted of a misdemeanor crime of domestic violence? “Yes” means you have such a conviction, which is a federal firearms disqualifier.
- 14k. Have you ever renounced your United States citizenship? “Yes” means you formally gave up U.S. citizenship.
- 14l. Are you an alien who is illegally or unlawfully in the United States? “Yes” means you're present without legal immigration status.
- 14m.1. Are you a non-citizen who was admitted to the U.S. on a nonimmigrant visa (for example, a tourist or student visa)? Lawful permanent residents / green-card holders answer “No.”
- 14m.2. Only if you answered “Yes” to 14m.1: do you fall within one of the exceptions listed in the form's instructions (such as a valid hunting license)? This is the one question where a qualifying applicant may answer “Yes.”
Answer every question honestly. Knowingly making a false statement on a federal firearms form is itself a felony. If any answer here isn't a clear “No,” stop and talk to an attorney before submitting — this section is educational, not legal advice, and only you know your own history.
7. Necessity Statement (SBR/SBS Only)
Field 13 is the necessity statement, and it only appears for short-barreled rifles (SBRs) and short-barreled shotguns (SBSs). It asks, in essence, why you need the item. The standard, accepted answer is simply “All lawful purposes.”
If you're buying a suppressor, you will not see this field at all — it doesn't apply to silencers. The StampSwap Prep Tool only shows the necessity statement when the item type requires it.
8. Personal Details the Form Needs
Beyond the yes/no questions, the form collects identifying information and supporting documents. In the StampSwap Prep Tool, the most sensitive of these (SSN, date of birth, place of birth, citizenship, alien number, UPIN) live only in your browser and are never stored on our servers. Here's what each one is and where to get it:
Passport-style photo
A 2×2 inch color photo meeting passport standards — front-facing, neutral expression, plain light background, taken recently. Pharmacies and shipping stores do these for a few dollars, and eForms accepts a digital upload.
Fingerprints
For eForms, you submit an EFT electronic fingerprint file. The easiest route is a fingerprinting kiosk — services like Silencer Shop have them — which captures your prints electronically for roughly $10-$65. If you file on paper, you use two physical FD-258 fingerprint cards instead.
Date & place of birth
Your date of birth (17b), state of birth (17c), and country of birth (17d). Straight off your ID or birth certificate.
Race & ethnicity (18)
A required demographic field on the federal form; you select all that apply. It's part of the standard identity data collected, not a screening question.
Social Security Number (17a)
Optional, but providing it helps the NICS background check run cleanly and can speed up processing (especially if you have a common name). Your call.
UPIN (16)
A Unique Personal Identification Number is only relevant if the FBI already issued you one after a prior NICS delay or challenge. If you don't have a UPIN, leave it blank — most people never get one.
Citizenship & alien admission number (15, 19)
U.S. citizens select the United States and skip the alien number. Non-citizens select their country of citizenship and enter their alien admission number (AR#, USCIS#, or I-94#) in field 15.
9. What Happens After You Certify
Once you've filled everything out and certified, here's the sequence:
- 1.The transferor (the seller, or the dealer in an interstate transfer) submits the Form 4 through eForms with you as the transferee.
- 2.You track the status in your eForms account — it moves through submitted, pending, and approved states. Current waits are around 10-15 days for individuals and 25-30 days for trusts.
- 3.When it's approved, you get an email and a digital tax stamp (a PDF) confirming the registration.
- 4.You pick up the item from the dealer. Bring a valid government photo ID. At pickup the dealer runs a standard Form 4473 and a NICS check, just like buying a regular firearm, and you must be at least 21 to take delivery through a dealer.
The seller keeps a copy of the approved Form 4 for their records. Never take possession before approval — transferring an NFA item without an approved Form 4 is a federal felony.
10. Glossary
- FFL
- Federal Firearms License(e). A licensed dealer authorized to handle firearm transfers.
- SOT
- Special Occupational Tax. An FFL who has paid the SOT can deal in NFA items — commonly called a Class 3 dealer.
- Form 3
- ATF 5320.3, the dealer-to-dealer transfer form. Used to move an item between FFL/SOTs (e.g., in an interstate sale) before your Form 4.
- Form 4
- ATF 5320.4, the tax-paid transfer application — the form this guide walks through. It transfers an NFA item to you.
- Form 5320.23
- The Responsible Person Questionnaire. Each responsible person of a trust or entity submits one with their own photo and fingerprints.
- 4473
- The Firearms Transaction Record you fill out at the dealer at pickup, which triggers a NICS check — the same form used for ordinary gun purchases.
- Tax stamp
- Proof that the NFA transfer tax was paid (now $0 for suppressors) and the transfer approved. Delivered as a PDF via eForms.
- eForms
- The ATF's online system for filing NFA forms electronically. Far faster than paper.
- NICS
- National Instant Criminal Background Check System — the FBI background check run on the transferee.
- NFRTR
- National Firearms Registration and Transfer Record — the federal registry where every NFA item and its owner are recorded.
- A&D book
- Acquisition & Disposition record. The bound log a dealer keeps of items received and transferred.
- Transferor / Transferee
- The transferor is the party giving up the item (seller or dealer); the transferee is the party receiving it (you, the buyer).
- Responsible person
- Anyone with authority over a trust or entity's NFA items; each files Form 5320.23.
- CLEO
- Chief Law Enforcement Officer — your local sheriff, police chief, or state AG, who is notified of (not asked to approve) your transfer.
Ready to prep your Form 4?
Use our step-by-step Form 4 guide, confirm your state allows the item, and start shopping listings.