Roes Welcome Sound is a long channel at the northwest end of Hudson Bay in Kivalliq Region, Nunavut, Canada between the mainland on the west and Southampton Island on the east. It opens south into Hudson Bay. Its north end joins Repulse Bay which is connected east through Frozen Strait to Foxe Basin, thereby making Southampton Island an island. Wager Bay is a western branch. It is situated 200 km (120 mi) north of Marble Island. Roes Welcome Sound measures 290 km (180 mi) long, and 24 to 113 km (15 to 70 mi) wide.
"On an inspection of the charts, I think it will also appear probable that a communication will one day be found to exist between this inlet (Prince Regent's) and Hudson's Bay, either through the broad and unexplored channel called Sir Thomas Roe's Welcome, or through Repulse Bay, which has not yet been satisfactorily examined."
Roes Welcome Sound is a bowhead whale migratory path, discussed in W. Gillies Ross' 1974 published paper, Distribution, Migration, and Depletion of Bowhead Whales in Hudson Bay, 1860 to 1915.