It holds records created by the municipal government and its amalgamated former municipalities from 1792 to the present day,[1] as well as non-government records created by private groups and individuals.

Of the 1.2 million photographs within the Toronto Archives collection, the oldest are a set of twenty-five prints of the city taken in 1856-57 by the firm of photographers, Armstrong, Beere and Hime.

It was designed by the architectural firm of Zeidler Roberts, who also designed the Toronto Eaton Centre, as a state-of-the-art purpose-built archives building incorporating a climate controlled records, a central atrium and exhibition area; a 60-seat lecture room and a Research Hall.

[6] The original purpose of the building was to hold the records of the government of Metropolitan Toronto.

[7] Prior to amalgamation, the archives were held in the respective city halls.