In the United States, the minimum age to own or purchase a firearm depends on the type of firearm and whether the purchase is from a licensed dealer or a private seller, as well as state laws:

• Federally, you must be at least 18 years old to purchase long guns (rifles and shotguns) and ammunition for them from licensed dealers

• To purchase handguns from licensed dealers, the minimum federal age is 21

• Many states impose additional restrictions, with some requiring purchasers to be 21 to buy any firearm, including long guns (e.g., California, Florida, Hawaii, Illinois, New York)

• Some states allow individuals aged 18 to 20 to purchase handguns in private sales, but licensed dealer sales still require the buyer to be 21

• For example, in Texas, federal law prohibits licensed dealers from selling firearms to anyone under 18, and handguns cannot be sold to anyone under 21; private sales have additional rules and parental consent may be required for minors

• In the UK, owning or purchasing a firearm requires a police-issued firearms certificate, regardless of age

In summary, the minimum age to own or buy a firearm is generally 18 for long guns and 21 for handguns under federal law, but state laws can impose stricter age limits and conditions. Parental consent and private sale exceptions may apply in some states