Primera Angostura is a sound of the Strait of Magellan in Tierra del Fuego. It is the narrowest part of the Strait between the island and the continent. The sound was named Primera Angostura (Spanish for First Narrows) as it was the first narrows of the strait that ships met when sailing through the strait from east to west.
The ferry company Transbordadora Austral Broom S.A. operates across the narrows.