This was the most numerous US submarine class. Nine of the 52 US submarines lost in World War II were of this class, along with five lost postwar, including one in Turkish service in 1953, one in Argentine service in the Falklands War of 1982, and one in Peruvian service in 1988. Also, Lancetfish flooded and sank while fitting out at the Boston Naval Shipyard on 15 March 1945. She was raised but not repaired, and was listed with the reserve fleet postwar until struck in 1958. Some of the class served actively in the US Navy through the middle 1970s, and one (Hai Pao ex-Tusk) is still active in Taiwan's Republic of China Navy.
Balao was able to operate in the range 13,000 miles surfaced, submerge 400f deep, and 75 days on patrol. She normally carries 10 officers and 70 crewmembers.