Do Brazil passport holders need a visa to visit AR?

No visa. Brazilian ordinary passport holders can enter Argentina visa-free for tourism for up to 90 days as Mercosur citizens. A valid Brazilian national ID card (RG/Carteira de Identidade) is accepted instead of a passport. Since July 1, 2025, all visitors must also carry proof of health insurance. Brazil and Argentina are both full members of Mercosur, so Brazilian citizens enjoy broad freedom of movement. A Brazilian ordinary passport holder needs no visa for tourism, business, or transit and is granted up to 90 days of stay on arrival. Uniquely, Brazilians do not even need a passport: a valid Brazilian national/state identity card (RG / Carteira de Identidade Nacional) is accepted at all Argentine entry points as a Mercosur travel document. Entry is free of charge, and the 90-day stay can typically be extended once at the Dirección Nacional de Migraciones (DNM/Migraciones) for an additional 90 days, or converted to Mercosur temporary/permanent residency, which Brazilians can apply for at any time. The one significant recent change: under Decree 366/2025, effective July 1, 2025, every foreign visitor entering Argentina (including Mercosur tourists) must present proof of valid health/medical insurance covering medical care, hospitalization, and repatriation for the full duration of the stay. Argentina is not in the Schengen area, so no Schengen 90/180 rule or ETIAS applies.