The Safir's first flight on 20 November 1945. The all-metal Safir was designed by Anders J. Andersson, who had previously worked for Bücker, where he designed the all-wood Bücker Bü 181 "Bestmann". The Safir thus shared many conceptual features of its design with the Bestmann.
323 units were built in 5 versions (A, B, B-2, C and D). The Safir was used by the Swedish, Norwegian, Finnish, Austrian, Tunisian and Ethiopean air forces as a trainer aircraft, and a single aircraft was used by the Japan Defense Agency as an STOL test platform.
During development of the Saab 29, the initial Saab 91 prototype was modified with a scaled-down version of the Saab 29's swept wings; this aircraft was designated Saab 201 Experimental Aircraft. This same airframe was later fitted with wings designed for the Saab 32 Lansen; this was designated Saab 202.
A single Saab 91 Safir was modified as the Saab X1G for research in Japan.