With over one thousand delivered, the Potez 63 series of aircraft were the most widely used of any other French design during the war. It was somewhat obsolescent by 1940 but nevertheless were to be found in the thick of combat, suffering heavy losses but compensating by the bravery of its crews who flew undaunted into the teeth of Luftwaffe fighter opposition. The Potez 63 series included day fighters, night fighters, reconnaissance, and light bombers, for both the Armée de l'Air and the Aéronavale making it arguably the most versatile warplane in the French arsenal. Due to its uncanny resemblance to the Bf 110, the Potez 63 was occasionally engaged by friendly aircraft, and by the time of the surrender over 400 had been destroyed in action mostly due to the lack of fighter cover available. Numerous surviving aircraft flew with the Free French, Germany, and Vichy forces over the Middle East and North Africa with additional production undertaken after the capitulation and other foreign operators of the type being Greece, Romania, and Switzerland.

The prototype Potez 630.01 first flew on 25 April 1936 and was followed by a period of production difficulties until the Potez 630 and 631 fighters entered service in 1938. Other variants include the Potez 633 light bomber which was used in the Eastern front by Rumanian forces, the Potez 637 with a ventral observation gondola for army cooperation missions, and the Potez 63.11 tactical recon aircraft distinguished by its fully glazed nose. It was the most widely produced version with units serving in both German and Vichy air forces after the surrender.