For the village, see Hańcza, Podlaskie Voivodeship.

Hańcza (Lithuanian: Ančia) is a lake in Suwałki Region, Podlaskie Voivodeship, Poland. It is 311.4 ha large, 4.5 km long and 1.2 km at its widest. It is the deepest lake in Poland with a maximum depth of 108.5 m. The Czarna Hańcza river flows through it.