Rockstar has not announced any age restriction for purchasing GTA 6. The game is rated by regional boards, and those ratings are typically revealed closer to release. As of now, no rating has been confirmed for any territory, so there is no official minimum purchase age tied to the game itself.
What is known is that GTA 6 launches on November 19, 2026, for PlayStation 5 and Xbox Series X|S, as detailed on the release date page. Past Grand Theft Auto titles have received Mature (17+) ratings in North America and PEGI 18 in Europe, but that is not a guarantee for this title. Retailers and digital stores may impose their own age checks, and those policies are not yet public.
If you are under 18, the practical answer is that you will likely need a parent or guardian to handle the purchase, but this is speculation until ratings are announced. Watch the price page or official channels for the first rating disclosure, which usually appears a few months before launch.