During late 1938, production of the M.S.406 commenced; the first production example performed its maiden flight on 29 January 1939. Production was initially quite slow to ramp up; only 18 aircraft were produced at Puteaux, along with 10 fighters built by SNCAO. Deliveries were hampered more by the slow deliveries of engines to power the type than by the lack of airframes themselves; while efforts were made to correct this, according to Botquin, the engine supply issue was present throughout the entire manufacturing programme. By April 1939, the production lines were delivering six aircraft per day, and when war officially broke out on 3 September 1939, the rate production had risen to 11 aircraft per day; at this time, 535 M.S.406s had entered squadron service. According to aviation author Gaston Botquin, the rate of production of the type was comparable to the initial model of the British Hawker Hurricane.