As Toronto grew, many street names were changed for a variety of reasons—to eliminate duplication when an area was annexed or confusion when streets were joined together, to commemorate a person or event, or to better reflect the community’s social standing. Before concluding that your family moved to a different street, check that the street name didn’t change instead.
The “streets” section of a city directory is a good place to find these changes noted.
Researcher Hugh Armstrong has created an online finding aid to street name changes around the 1901 census. Please note that many changes have occurred since that time.
The City of Toronto Archives has finding aids to street name changes in its research hall for the former municipalities that now make up Toronto.
The Scarborough Historical Society includes a list of street name origins and changes on its website.