Written & reviewed by External Legal AI · Published July 2, 2026
Two layers of law govern every gun purchase. Federal law sets the nationwide floor — the dealer paperwork, the background check, the age minimums, and the list of people who may not possess guns at all. State law then builds on top of that floor, and the additions vary enormously: some states add purchase permits, waiting periods, or background checks for private sales, while others add almost nothing.
Every purchase from a federally licensed dealer starts with ATF Form 4473, on which the buyer certifies — under penalty of federal law — that they are the actual buyer and not a prohibited person. The dealer then runs the buyer through the FBI's National Instant Criminal Background Check System (NICS) before handing over the firearm. Lying on the form is a federal felony, and that includes 'straw purchases': buying a gun for someone who cannot buy it themselves.
Federal law (18 U.S.C. § 922(g)) bars gun possession by people convicted of a crime punishable by more than a year in prison (most felonies), people with a misdemeanor domestic-violence conviction or a qualifying restraining order, unlawful users of controlled substances — which federally includes marijuana even where a state has legalized it — fugitives, people who have been involuntarily committed or adjudicated mentally incompetent, people dishonorably discharged from the military, and people unlawfully present in the country.
From a licensed dealer, federal law requires buyers to be 18 for rifles and shotguns and 21 for handguns. Since the 2022 Bipartisan Safer Communities Act, buyers under 21 also get an enhanced background check that reaches juvenile and mental-health records and can take extra days. States are free to set higher age limits, and several do.
Federal law does not require a background check when one private resident sells to another within the same state — but the seller may not transfer a gun to someone they know or have reason to believe is prohibited, and sales across state lines generally must route through a licensed dealer. On top of that federal baseline, many states require background checks or dealer processing for every sale, including private ones, while others leave in-state private sales largely unregulated.
Some states require a permit or license before you may purchase at all, impose waiting periods of several days between purchase and pickup, or restrict specific categories of firearms and magazines. These rules differ sharply from state to state and change frequently, so the state police or attorney general's official page — not a forum or a store clerk's recollection — is the place to confirm what applies where you live.
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