Most transportation historians date the history of Canada's railways as beginning on February 25, 1832, with the incorporation of British North America's first steam-powered railway, the Champlain and St. Lawrence Railroad (C&SL). This line opened for traffic on July 21, 1836, although there are cases of animal-drawn mining tramways in Nova Scotia from the 18th century onward.

Thousands of railways followed the C&SL and were given a charter by the federal or provincial governments, although in most cases these charters never resulted in an actual line being constructed. Many of these charters were so-called "paper railways" and were absorbed into other railways, that is they existed on paper with the actual trains bearing the name of another railway or system of railways. For example, Canadian National Railways alone consisted of over some 400 railways (see List of Canadian National Railways companies).

The reason for these "paper" railways was the ease of getting a charter. This was often done by a major railway such as Canadian Pacific Railway or Grand Trunk Railway, but the true interests were kept hidden to keep attention away from the efforts of competing major railways to gain access to another's territory. In other instances local interests wanted a railway to connect their community with the main line of a major railway that did not enter their town, or to connect to another major railway for competitive reasons, to get lower freight rates, something that remains to this day. In many cases these local efforts were quickly taken over by a major railway to both expand its own network and to deny its competition access to traffic.

Streetcar and interurban railways were chartered provincially, in the case of Ontario under the Street Railway Act.

Railways that were not common carriers did not require a charter under the Railway Act since they were used primarily for the owners' own purposes, mainly logging and mining.

American railroads always operated in Canada under charters of subsidiary railways even though most had equipment lettered only for the parent company. Most U.S. railroads also operated in Canada through subsidiary railways with one exception: Wabash Railway which had not a mile of track in Canada as it crossed southern Ontario using trackage rights granted by the Grand Trunk Railway of Canada. These rights still exist with present-day Canadian National and Norfolk Southern, which runs into Windsor and Sarnia, Ontario. It formerly ran through Montreal, Quebec, but service was stopped due to such services causing traffic congestion.

This list of defunct railways includes only those railways that actually came into existence. Many were taken over by other railways or had a name change and thus continued to operate trains over the same tracks. A few ceased to exist because they went out of business and were abandoned and dismantled.

For simplicity on this list, Canadian National Railways (CNR) (pre-1960), Canadian National Railway (CN) (post-1960), Canadian Pacific Railway (CPR), Grand Trunk Railway (GTR), and Canadian Northern Railway (CNoR) will be abbreviated for notations. Others will be abbreviated as required.

Also consult the list of active Canadian railways.

A Railway name Locale Operating years Comments Alberta Railway and Navigation Company Lethbridge, Alberta to Great Falls, Montana 1889–1912 Acquired by CPR. Alberta and Great Waterways Railway Alberta, British Columbia 1929–1981 Acquired by NAR. Albion Mines Railway Pictou County, Nova Scotia 1829–c.1890 First railway and first use of metal rails in British North America; horse-drawn until 1838. Abandoned. Algoma Central Railway Algoma and Cochrane Districts, Northeastern Ontario 1899–1995 Acquired by WC. Algoma Eastern Railway Algoma and Sudbury Districts, Northeastern Ontario 1911–1930 Acquired by CPR on July 14, 1931 by 999-year lease. Alma and Jonquières Railway Herbertville, Quebec and Lake St. John to a point between Grand Decharge and Petite Decharge and from St. Joseph d'Alma to Jonquière 1912–1937 Merged into RS.Athabasca Northern Railway Alberta 2000–2007 Reacquired by CN. Atlantic and North-West Railway southeastern Quebec, central Maine Acquired by CPR. Atlantic, Quebec and Western Railway Gaspé Peninsula, Quebec 1907–1923 Acquired by CNR.

B Railway name Locale Operating years Comments Bay of Quinte Railway southeastern Ontario 1897–1910 Acquired by CNoR. Berlin and Waterloo Street Railway Kitchener and Waterloo, Ontario 1889–1919 Continued operations and renamed to Kitchener and Waterloo Street Railway. Botwood Railway central Newfoundland 1908-1956 Subsidiary of AND. Sold to become GFC. Brantford, Hamilton and Western Railway British Columbia Electric Railway Owned by BCH. Sold to become SRY. British Columbia Railway British Columbia 1972–2004 Acquired by CN. Brockville and Ottawa Railway eastern Ontario Acquired by CPR. Brockville, Westport and North-Western Railway eastern Ontario Acquired by CNoR. Bruce Mines and Algoma Railway Buchans Railway central Newfoundland Owned by ASARCO. Abandoned. Buctouche and Moncton Railway southeastern New Brunswick Acquired by CNR. Burlington Northern Manitoba Limited central Manitoba 1971–1999 Subsidiary of BN. Renamed to BNSFM. Bytown and Prescott Railway eastern Ontario 1854–1884 Leased by CPR for 999 years. Abandoned in 1995.

C Railway name Locale Operating years Comments Canada and Gulf Terminal Railway eastern Quebec ?-1975 Acquired by CN. Calgary and Edmonton Railway Acquired by CPR. Campbellford, Lake Ontario and Western Railway Acquired by CPR. Canada Air Line Railway Subsidiary of GWR. Canada Atlantic Railway central, eastern Ontario, western Quebec 1890–1914 Acquired by GTR. Canadian Atlantic Railway Quebec via Maine to New Brunswick 1988–1994 Part of CPR mainline east of Lac-Mégantic, divested 1994 as Canadian American Railroad (bankrupt 2001) and later MM&A (bankrupt 2013). Portion east of Brownville is Irving's New Brunswick Southern Railway. Canadian American Railroad Quebec to Maine 1994–2002 Iron Road Railways segment of CP's former Canadian Atlantic Railway from Lennoxville to Brownville, Maine, bankrupt 2001. Canadian Pacific British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec 1881–2023 Acquired and Merged with the Kansas City Southern Railroad to form CPKC. Canada Central Railway Acquired by Canadian Pacific. Canada Coal and Railroad Company northwestern Nova Scotia 1905–1906 Sold to become MCR&PC. Canada Coals and Railway Company northwestern Nova Scotia 1892–1905 Sold to become CC&RC. Canada Southern Railway Acquired by MCRR, later NYC. Sold to CPR and CN. Abandoned. Canadian Atlantic Railway eastern Quebec, Maine, western New Brunswick, western Nova Scotia 1988–1994 CPR subsidiary created to operate lines east of Montreal including DAR. Portions abandoned or sold by 1994 to NBSR, EMR, CDAC, and WHRC. Canadian Government Railways Maritimes, Quebec, Ontario, Manitoba 1915–1918 Entrusted to CNR. Corporate entity sold to CN in 1993 for $1. Canadian National Electric Railways Division of CNR. Canadian Pacific Electric Lines Division of CPR. Canadian Northern Railway Nova Scotia, Quebec to British Columbia 1899–1918 Nationalized into CNR. Canadian Northern Alberta Railway Constituent company of CNoR. Canadian Northern Branchlines Company Constituent company of CNoR. Canadian Northern Consolidated Railways Constituent company of CNoR. Canadian Northern Manitoba Railway Constituent company of CNoR. Canadian Northern Montreal Tunnel and Terminal Company Constituent company of CNoR. Canadian Northern Ontario Railway Constituent company of CNoR. Canadian Northern Pacific Railway Constituent company of CNoR. Canadian Northern Quebec Railway Constituent company of CNoR. Canadian Northern Saskatchewan Railway Constituent company of CNoR. Canadian Northern Western Railway Constituent company of CNoR. Cape Breton Development Corporation Railway Sold to SCR. Cape Breton Railway Cape Breton Eastern Extension Railway Stellarton to Sydney, NS 1890 Constituent part of IRC Caraquet Railway northeastern New Brunswick Acquired by CNR. Central Canada Railway Central Maine and Quebec RailwayQuebec, Maine, Vermont2014-2020Acquired by Canadian Pacific Railway Central Ontario Railway Acquired by CNoR. Central Railway of New Brunswick Acquired by CPR. Central Vermont Railway Also a defunct U.S. railroad. Subsidiary of GTR, later CNR. Became NECR. Champlain and St. Lawrence Railroad southwestern Quebec 1836–1857 First common carrier railway in British North America. Acquired by M&CR. Chatham, Wallaceburg and Lake Erie Railway Interurban railway. Columbia and Kootenay Railway Acquired by CPR. Columbia and Western Railway Acquired by CPR. Cornwallis Valley Railway Kentville to Kingsport, NS 1890-1892 Acquired by W&AR. Credit Valley Railway Toronto to St. Thomas, ON Acquired by CPR. Cumberland Railway and Coal Company Springhill Junction to Parrsboro, NS 1883-1962 Abandoned.

D Railway name Locale Operating years Comments Detroit River Tunnel Company Subsidiary of CASO/MCRR. Devco Railway Cape Breton, NS 1968-2001 Former DOSCO coal hauler, assets acquired by Sydney Coal Railway Dominion Atlantic Railway western Nova Scotia 1894–1994 Acquired by CPR in 1912, after 1988 was operated as part of CAR. Sold to become WHRC. Dominion Coal Company Dominion Timber and Minerals Railway Laurentian Mountains (Western Quebec) Kilmar, Black Lake, Lachute, Marlean 1916-1981 Subsidiary of CRL. Duluth, Winnipeg and Pacific Railway Minnesota to Winnipeg Manitoba / Port Arthur ON Originally a CNoR railway by the name of Duluth, Rainy Lake and Winnipeg Railway. Now a subsidiary of CN - by way of GT and then merged with WC (both are CN companies).

E Railway name Locale Operating years Comments Edmonton, Dunvegan and British Columbia Railway Acquired by NAR. Edmonton Interurban RailwaySt Albert to EdmontonSeptember 1913 - April 1914Abandoned after car barn burned down. Rails dismantled in 1917 and sold for scrap. Edmonton Yukon and Pacific Railway Acquired by CNoR. Elgin and Havelock Railway central New Brunswick Acquired by CGR. Erie and Ontario Railway Acquired by CASO. Esquimalt and Nanaimo Railway Acquired by CPR. Sold 2006 to become Southern Railway of Vancouver Island. European and North American Railway southern New Brunswick 1857–1872 Eastern extension merged into IRC. Western extension became part of NBR. Englewood Railway Northern Vancouver Island 1917-2017 Sold to Western Forest Products 2006.

F Railway name Locale Operating years Comments Fredericton and Grand Lake Railway central and western New Brunswick Acquired by CPR.

G Railway name Locale Operating years Comments Galt and Preston Street Railway Cambridge, Ontario 1894–1908 Renamed the Galt, Preston, and Hespeler Street Railway after Hespeler line was built. Galt, Preston and Hespeler Street Railway Cambridge, Ontario 1894–1908 Merged into the Berlin, Waterloo, Wellesley, and Lake Huron Railway. Georgian Bay and Seaboard Railway Acquired by CPR. Glengarry and Stormont Railway Grand Falls Central Railway central Newfoundland 1956–1977 Abandoned. Grand River Railway Waterloo Region, Ontario 1914–1931 Acquired by CPR, merged into CPEL. Grand Trunk Pacific Railway Manitoba, Saskatchewan, Alberta, British Columbia 1914–1920 Nationalized into CNR. Grand Trunk Railway Ontario, Quebec, New England 1852–1923 Nationalized into CNR. Great North West Central Railway Acquired by CPR. Great Northern Railway (U.S.) A trans U.S. railway that had a railway in the BC Fraser Valley competing with CP for the natural resources. Great Northern Railway of Canada 1892-1907 between Rivière-à-Pierre, Quebec, and Hawkesbury, Ontario Great Western Railway southwestern Ontario 1853–1884 Acquired by GTR Guelph and Goderich Railway Acquired by CPR.Gunflint and Lake Superior RailroadLakehead Region (Ontario and Minnesota)1902–1909

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