The Spitfire was conceived by Standard-Triumph to compete in the small sports car market against the Austin-Healey Sprite. The Sprite had used the drive train of the Austin A30/A35 in a lightweight body. The Spitfire used mechanicals from the Herald saloon/sedan. Where the Austin A30 used monocoque construction, the Herald used body-on-frame — a chassis Triumph was able to downsize from the Herald, saving the cost of developing a completely new chassis-body unit.

Giovanni Michelotti, who had designed the Herald, styled the bodywork, which featured wind-up windows (in contrast to the Sprite and Midget, which used side curtains) and a cowl composed of the bonnet/hood and wings/fenders that opened forward for engine access. The Spitfire's introduction was delayed by its company's financial troubles in the early 1960's and was subsequently announced shortly after Standard Triumph was taken over by Leyland Motors. When Leyland officials, taking stock of their new acquisition, found Michelotti's prototype under a dust sheet in a factory corner, it was quickly approved for production.

The first cars were sold in 1962 and the model went through a series of revisions over the years with the fifth and last revision, The Spitfire 1500, remaining in production until 1980.