Naupactus is situated on a bay on the north coast of the Gulf of Corinth, 3 km west of the mouth of the river Mornos. The harbour is accessible only to the smallest craft.
It is 9 km northeast of the Bridge Rio-Antirrio, which is connecting mainland Greece to Peloponnese on the western part of the Gulf of Corinth. The Greek National Road 48/E65 (Antirrio – Naupactus – Delphi – Livadeia) passes north of the town.
