Which strait connects Hudson Bay to the Labrador Sea?

The strait that connects Hudson Bay to the Labrador Sea is Hudson Strait.

Hudson Strait lies in northern Canada between Baffin Island and Nunavik, linking Hudson Bay with the Labrador Sea and the North Atlantic. Its eastern entrance is near Cape Chidley, while the western end opens into Hudson Bay near Southampton Island.

The waterway became important during European searches for the Northwest Passage. English navigator Martin Frobisher reported entering it in 1578, though he initially called it “Mistaken Strait” because he doubted it offered the route he wanted. Later, the Hudson’s Bay Company used the strait as the principal sea approach to its trading network.

The names in the question can be confusing because Hudson Bay and the Labrador Sea are bodies of water, not straits. Davis Strait is a separate passage east of Baffin Island, connecting the Labrador Sea with Baffin Bay. Hudson Strait is also heavily affected by seasonal sea ice, which historically restricted navigation to part of the year.