Five soldiers went missing Aug. 15 when their UH-60 Black Hawk went down during routine night training.
Searchers have continued to find debris, but the two pilots and three crew members have not been found. The names of the crewmen have not been made public by the Army.
"A decision to suspend searching without finding survivors is extremely difficult given the depth of its impact, and I know I speak for the entire Coast Guard when I say our thoughts and prayers are with Army helicopter squadron and particularly with families and loved ones of those missing," Rear Adm. Vincent B. Atkins, commander of Coast Guard 14th District, said in a statement.
The lengthy search for survivors covered a vast area -- more than 96,000 square miles -- and involved more than 132 separate searches, the Coast Guard said.
The search started just a few miles off Kaena Point, the most northwest point of Oahu, but by the weekend was extended beyond the Hawaiian islands of Kauai and Niihau, based upon computer modeling that estimated the possible drift of survivors caught in the ocean currents, the Coast Guard said.