It is the oldest purpose-built post office in Canada that functioned as a department of the British Royal Mail, and the only surviving example.

After its initial use as a post office, it became part of a Roman Catholic boys' school (De La Salle College) and later a cold storage building.

Located at 260 Adelaide Street East in downtown Toronto, the building now houses a museum and a full-service post office, run by the Town of York Historical Society.

[6] Toronto's First Post Office is operated by the Town of York Historical Society.

It was originally a three-storey building, with two front doors, one for the private residence and one for the post office proper.