Although it is quite close to the open Atlantic (separated only by Hudson Strait), Ungava Bay is part of the Arctic Ocean.

suggest that Ungava Bay may be the remnant of an impact crater (age unknown) approximately 225 km (140 mi) in diameter.

[3] Some sources estimate the spring tide range at the mouth of the Leaf River as being as high as 17 m (56 ft).

Due to the influence of the Labrador Current, summers are too cold for tree growth and all the land surrounding the bay is treeless tundra.

Ungava Bay is surrounded by numerous Inuit villages, the largest of which is Kuujjuaq, at the mouth of the Koksoak River.