Toronto Subway is based on the lettering originally used for station identification and signage in the Toronto, Canada, subway system, which first opened to the public in 1954.

Over the years and subsequent expansion of the subway, the signage has been corrupted by the use of other sans typefaces such as Helvetica, Univers and Gill Sans. However, the original lettering remains unique. The lettering on the original signage consists only of uppercase characters and a few bits of punctuation in two weights.

The Toronto Subway fonts were developed from rubbings of the lettering on station walls and photographs of painted signage. The overall style of the lettering is very mechanical, almost naive, yet still having a certain amount of elegance, and this style was followed as much as possible in developing the companion lowercase, extended characters and extra punctuation.