"Chickadee" cleared Naval Station Charleston, South Carolina, on 7 April for Milford Haven, Wales, arriving there on 12 May. For the remainder of the month, the minesweeper engaged in training exercises for the coming invasion of Europe. Arriving off Normandy on 5 June 1944, "Chickadee" swept fire support channels into Baie de la Seine and throughout the various assault areas along the French coast in support of Operation Overlord, the Normandy Invasion. She performed her hazardous duties under enemy shore fire on several occasions, but escaped with only minor damage from shrapnel and no casualties. The ship assisted in the rescue of survivors from and , and towed the damaged LST to safety.