Foz is a town and municipality in A Mariña country in the Galician province of Lugo. It has been historically linked to the Ancient Province of Mondoñedo and also linked to the arrival of Briton immigrants during the Dark Ages (5th and 6th centuries) fleeing by sea from the British Isles (see Bishop Maeloc, Britonia and San Martiño de Mondoñedo) It has 9800 inhabitants. It borders the municipalities of Burela and Barreiros, and to interior with the municipalities of Lourenzá, Mondoñedo, O Valadouro, Alfoz and Cervo.

Foz is a coastal town on the shores of the Cantabrian Sea at the mouth of the river Masma, where it forms the Foz estuary, with an approximate area of 100 km².

Although Foz was previously a fishing village, now the major part of its economic resources is from tourism.