50 were produced, 20 P-59A's and 30 P-59B's. The aircraft had a lot of problems and never saw combat. It compared unfavorably to the British jet prototype and Americans would rather fly the Mustang. Still, the US got valuable experience and knowledge out of the project.
The competing Lockheed P-80 was more successful, but also was not operational by the end of the war. At least the Gloster Meteor got into combat.