Australia, China, and the United States used the P-43.
China received 51 / 103 of the P-43A-1s. These had problems with the turbochargers and self sealing fuel tanks.
The Royal Australian Air Force (RAAF) received eight P-43s in 1942 to be used as photo reconnaissance aircraft. Six of these survived to be turned over to the United States Army Air Force (USAAF) in 1943.