Question 21 on Form 4473 is the buyer eligibility section. It's where the buyer certifies under penalty of law that they are not a prohibited person under federal law. It's also where a significant portion of ATF audit violations come from — blank sub-questions, inconsistent answers, and missing buyer signatures.
Every Sub-Question Must Be Answered
Question 21 has multiple sub-questions labeled 21a through 21n. Every single one must be answered with a "yes" or "no." There are no optional fields. A blank sub-question — even one the buyer skipped accidentally — is an error on the face of the form. ATF auditors check every sub-question.
The Key Prohibitions
The sub-questions cover the federal prohibited person categories under 18 U.S.C. § 922(g) and (n). In plain language, these prohibit transfers to:
- Persons under indictment for or convicted of a felony (21b, 21c)
- Fugitives from justice (21d)
- Unlawful users of controlled substances (21e)
- Persons adjudicated as mentally defective or committed to a mental institution (21f)
- Illegal aliens (21g)
- Persons who have renounced U.S. citizenship (21h)
- Persons subject to certain domestic violence restraining orders (21i)
- Persons convicted of a misdemeanor crime of domestic violence (21j)
Question 21e — Marijuana: This is frequently misunderstood. Federal law still classifies marijuana as a controlled substance. A buyer who uses marijuana — even in a state where it is legal — answers "yes" to 21e and is prohibited from receiving a firearm. State legalization does not change the federal prohibition.
The Buyer Signature and Date
After completing Question 21, the buyer must sign and date the certification at the bottom of Section B. A missing buyer signature is a violation. A missing date is a violation. Both are among the most commonly cited errors during ATF audits.
What to Do When a Buyer Answers "Yes"
If a buyer answers "yes" to any of the prohibiting sub-questions, the transfer cannot proceed. Do not complete the transfer. The form should be retained. Do not attempt to coach the buyer on how to answer the questions.
Dealer Responsibility
As a dealer, you are not expected to independently verify the buyer's answers — that's NICS's job. But you are responsible for ensuring all fields are completed before the transfer. A Form 4473 with blank sub-questions in Question 21 is a compliance violation regardless of whether the buyer was actually eligible.
Know Every Form Is Clean Before Your Next ATF Audit
4473 Pro audits every field on every Form 4473 — Sections A through E. Catch errors before an ATF auditor does..
Get Started ›