It is the southernmost major (mainly) east-west road in the eastern portion of Toronto, specifically in the district of Scarborough, and runs east to Ajax in Durham.

Until Highway 401 was constructed, Kingston Road was the principal route from Toronto to points east.

The southwesternmost section in the Beaches area is a traditional urban street with storefronts, high pedestrian traffic, and streetcars.

The Toronto section runs from Queen Street East, as a continuation of Eastern Avenue, just west of Woodbine Avenue (route to Lake Shore Boulevard, the westerly continuation of former Highway 2), through Scarborough to Toronto's eastern city limits with Durham Region, where it continues into Pickering and Ajax (as Durham Regional Highway 2), and officially ends where its name changes to Dundas Street in Whitby, at Lake Ridge Road (Durham Regional Road 23), just west of Highway 412.

To preserve the historic village of West Hill, Kingston Road was realigned near the Highland Creek, east of Morningside Avenue.

From 1875 to 1887 Kingston Road Tramway ran horsecars from Don River (Don Bridge - now Old Eastern Avenue Bridge) to Main Street (moved further east to Blantyre Avenue in 1878 to serve Scarboro' Heights Hotel[6]).

[7] The single track route had three major stops (Don Bridge, Woodbine, Ben Lamond Hotel at Main Street and Scarboro Heights Hotel at Blantyre Avenue) running 12 times daily and 13 on Saturday in summer.

[7] The line was extended in stages, reaching its furthest extent east of Morningside Avenue in West Hill[7] in 1906.

The TTC assumed tracks on the line in 1922 and converted service as far as the newly constructed Bingham Loop (Victoria Park) to double-track city streetcars by the end of the year, and to Birchmount Loop in 1928, with radial service continuing in each case beyond.

The routes that primarily serve the street are: Toronto (TTC): Durham Region (DRT): GO Transit: