List of former provincial highways in Ontario

Ontario, Canada, has an extensive network of Primary (King's), Secondary, and Tertiary Highways, with county-level and city-level roads linking between them. Over the years, however, Ontario has turned back highways to the local authorities, renumbered them, or upgraded them to 400-series highways.

In 1997 and 1998, many sections of the provincial highway network were downloaded to local municipalities (such as cities, counties or regional municipalities) by the Ontario Ministry of Transportation as a cost-saving measure. While highways were occasionally transferred to local governments in the past, the 1997-1998 downloads represented the most significant changes to Ontario's highway network. Many highways were completely devolved, while of others only short sections remain under provincial jurisdiction (Highway 2, once stretching across Southern Ontario, now is only a few kilometres long). Below is a partial list of partially or wholly devolved highways since 1997.

Primary highways

* remains.
*. Was once an expressway in the 1940s until Highway 401 took over its current route in 1952.
* Highway 2A (Essex County, Ontario) (1929)
*.
* – Downloaded portions: south of the interchange with Highway 401, and north/east of Highway 8
*
*
* – Downgraded the portion in York Region west of Main St. Markham/ Markham Rd./Highway 48.
*
*
*.
* nowadays
*, and Oriole Parkway.
* are still signed as 11B.
* right-of-way.
* to Highway 62 near Foxboro.
*'s former routing.
*). Now Only a short stub remains.
*
*
*. The section from Tillsonburg to Highway 401 remains.
*.
* – Portions South of Highway 402
*
*.
*
*.
*
*.
*
*
*
*, near Seeleys Bay; now referred to as Leeds and Grenville County Road 32
*
*
* to Highway 28 at Burleigh Falls.
* to Highway 7 near Sharbot Lake; now referred to as Frontenac County Road 38
*.
*.
* deleted in 1998--Perth to Smith Falls section was Highway 15 prior to completion of Highway 7 in 1950s.
* (1938-1997)
*.
* Rd. 46.
* to Highways 7 & 12 south of Greenbank.
*.
*
*.
*.
* – East of Alberton to Highway 8 at Peters Corners.
* to Eastwood.
*
*
*.
*
*.
*
* – renamed Highway 6 from Hepworth to Springmount.
*
*.
*
*
*
*
*
*
*
*
*
*.
*
*.
*
*
*
*.
* (which paralleled Highway 98 for the majority of its length).
*
*.
*.
* – to Grand Valley from Highway 9, then Highway 25.
* in Ruthven. Now Essex County Road 45.
*, to Highway 98 (Now Essex County Road 46). Part of road is still signed as "Old HWY 114" from Manning Road (Essex County Road 19) to Provincial Road (Essex County Road 46).
* to Dorset.
*
*. Eastward is renamed Highway 118.
*. (The part between Highway 401 and the south Thames River had no name, while a half-mile section from the Thames to Hamilton Road was the Wenige Expwy, and north from there was Highbury Avenue.)
*.
* – Renamed Highway 28 when that road was re-routed and fully absorbed Highway 134.
* and former Highways 2 & 4. Now called Exeter Road.
*. Formerly Highway 24.
*.
* to Gravenhurst.

Additional highways and bypass routes devolved: 2B, 2S, 3B, 4A, 5A, 7B, 8A, 11B, 12B, 13, 15A, 16, 17A, 17B, 24A, 35B, 40B, 48B.

econdary highways

*Highway 517 – Used to run from Boulter to Combermere at Highway 62. Downgraded to County Rd. status in Hastings and Renfrew counties.
*Highway 543 – Highway 69 to Dew Drop Road in Sudbury. Downloaded in 1973 upon the creation of the Regional Municipality of Sudbury as Long Lake Road, part of Regional Road 80. Now designated Greater Sudbury Municipal Road 80.
*Highway 544 – Downtown Sudbury to Cartier. Redesignated as Highway 144 in 1965, as extension to Timmins was under construction.
*Highway 549 – Whitefish to Lake Panache in the town of Walden; downloaded in mid-1980s and now designated as Greater Sudbury Municipal Road 10.
*Boulter Road was an un-numbered secondary highway from at least the 1930s. It was downloaded in 1998, with its more-well-known brother road, Highway 517.
*Highway 550B – Sault Ste. Marie business route linking Highway 550 with the Sault Ste. Marie International Bridge. Returned to original city street names when Ontario decommissioned the B-series highways.
*Highway 646 – Linking Highway 599 with sites in the township of Pickle Lake. Now identified on signage as Pickle Lake Road.

Recycling

Highway numbers have even been "recycled" (used more than once on a provincial highway), however the use tends to be as far as possible from the original routing, and generally a few decades' time separate each numbering, to minimize confusion.

* Highway 77 (Ontario)

Highway stubs

This section will list all highways that have lost segments of their routings, are in at least two parts (or in the case of Highway 7 for a while, three parts), or have been truncated short of their original termini. Examples of this are Highway 3, Highway 4 and Highway 7.