| Name | Mark | System[1] | From | To | Successor | Notes | 
|---|
| Androscoggin Railroad |  | MEC | 1848 | 1911 | Maine Central Railroad | 
| Androscoggin and Kennebec Railroad |  | MEC | 1845 | 1862 | Maine Central Railroad | 
| Aroostook Northern Railroad |  | BAR | 1897 | 1901 | Bangor and Aroostook Railroad | 
| Aroostook River Railroad |  | CP | 1873 | 1989 | N/A | 
| Aroostook Valley Railroad | AVL |  | 1902 | 1996 | N/A | Electric until 1946 | 
| Atlantic and North-West Railway |  | CP | 1886 | 1994 | Canadian American Railroad | 
| Atlantic and St. Lawrence Railroad |  | CN | 1845 | 1960 | Canadian National Railway | 
| Bangor and Aroostook Railroad | BAR | BAR | 1891 | 2003 | Montreal, Maine and Atlantic Railway | 
| Bangor and Katahdin Iron Works Railway |  | BAR | 1881 | 1901 | Bangor and Aroostook Railroad | 
| Bangor, Oldtown and Milford Railroad |  | MEC | 1855 | 1870 | European and North American Railway | 
| Bangor and Orono Railroad |  | MEC | 1847 | 1850 | Penobscot Railroad | 
| Bangor and Piscataquis Railroad |  | BAR | 1861 | 1899 | Bangor and Aroostook Railroad | 
| Bangor and Piscataquis Canal and Railroad Company |  | MEC | 1833 | 1855 | Bangor, Oldtown and Milford Railroad | 
| Belfast and Moosehead Lake Railroad | BML | MEC | 1868 | 2001 | N/A | Continues as a tourist railroad[2] | 
| Belfast & Moosehead Lake Railway |  | MEC | 1867 | 1868 | Belfast and Moosehead Lake Railroad | 
| Boston and Maine Corporation | BM | B&M | 1963 |  |  | Still exists as a lessor of Pan Am Railways operating subsidiary Springfield Terminal Railway | 
| Boston and Maine Railroad | B&M, BM | B&M | 1844 | 1964 | Boston and Maine Corporation | 
| Bridgton and Harrison Railway |  |  | 1927 | 1941 | N/A | 
| Bridgton and Saco River Railroad |  | MEC | 1881 | 1930 | Bridgton and Harrison Railway | 
| Buckfield Branch Railroad |  | MEC | 1847 | 1863 | Portland and Oxford Central Railroad | 
| Bucksport and Bangor Railroad |  | MEC | 1873 | 1882 | Eastern Maine Railway | 
| Calais Railroad |  | MEC | 1838 | 1849 | Calais and Baring Railroad | 
| Calais Railway |  | MEC | 1832 | 1838 | Calais Railroad | 
| Calais and Baring Railroad |  | MEC | 1849 | 1870 | St. Croix and Penobscot Railroad | 
| Canadian American Railroad | CDAC |  | 1994 | 2003 | Montreal, Maine and Atlantic Railway | 
| Canadian Atlantic Railway |  | CP | 1988 | 1994 | Canadian American Railroad, Eastern Maine Railway | 
| Canadian National Railway | CN | CN | 1923 | 1989 | St. Lawrence and Atlantic Railroad | 
| Canadian Pacific Railway | CP | CP | 1886 | 1988 | Canadian Atlantic Railway | 
| Consolidated European and North American Railway |  | MEC | 1872 | 1880 | European and North American Railway | 
| Dexter and Newport Railroad |  | MEC | 1853 | 1939 | Maine Central Railroad | 
| Dexter and Piscataquis Railroad |  | MEC | 1888 | 1939 | Maine Central Railroad | 
| Eastern Railroad |  | B&M | 1847 | 1890 | Boston and Maine Railroad | 
| Eastern Maine Railway |  | MEC | 1882 | 1936 | Maine Central Railroad | 
| European and North American Railway |  | MEC | 1880 | 1955 | Maine Central Railroad | 
| European and North American Railway |  | MEC | 1850 | 1872 | Consolidated European and North American Railway | 
| Eustis Railroad |  | MEC | 1903 | 1911 | Sandy River and Rangeley Lakes Railroad | 
| Fish River Railroad |  | BAR | 1901 | 1903 | Bangor and Aroostook Railroad | 
| Franklin and Megantic Railroad |  | MEC | 1884 | 1897 | Franklin and Megantic Railway | 
| Franklin and Megantic Railway |  | MEC | 1897 | 1908 | Sandy River and Rangeley Lakes Railroad | 
| Franklin, Somerset and Kennebec Railway |  |  | 1897 | 1901 | Wiscasset, Waterville and Farmington Railroad | 
| Georges Valley Railroad |  |  | 1889 | 1919 | Knox Railroad | 
| Grand Trunk Railway | GT | CN | 1853 | 1923 | Canadian National Railway | 
| Great Falls and South Berwick Branch Railroad |  | B&M | 1841 | 1865 | Portsmouth, Great Falls and Conway Railroad | 
| Houlton Branch Railroad |  | CP | 1867 | 1989 | N/A | 
| International Railway of Maine |  | CP | 1881 | 1886 | Atlantic and North-West Railway | 
| Kennebec Central Railroad |  |  | 1889 | 1929 | N/A | 
| Kennebec and Portland Railroad |  | MEC | 1836 | 1864 | Portland and Kennebec Railroad | 
| Kennebec Valley Railroad |  | MEC | 1903 | 1904 | Somerset Railway | 
| Kennebec and Wiscasset Railroad |  |  | 1854 | 1873 | Wiscasset and Moosehead Lake Railroad | 
| Kennebunk and Kennebunkport Railroad |  | B&M | 1882 | 1919 | Boston and Maine Railroad | 
| Kingfield and Dead River Railroad |  | MEC | 1893 | 1897 | Kingfield and Dead River Railway | 
| Kingfield and Dead River Railway |  | MEC | 1897 | 1908 | Sandy River and Rangeley Lakes Railroad | 
| Knox Railroad |  |  | 1919 | 1932 | N/A | 
| Knox and Lincoln Railroad |  | MEC | 1864 | 1890 | Penobscot Shore Line Railroad | 
| Knox and Lincoln Railway |  | MEC | 1891 | 1901 | Maine Central Railroad | 
| Leeds and Farmington Railroad |  | MEC | 1865 | 1874 | Maine Central Railroad | 
| Lewiston and Auburn Railroad |  | CN | 1872 |  |  | 
| Lewy's Island Railroad |  | MEC | 1854 | 1870 | St. Croix and Penobscot Railroad | 
| Lime Rock Railroad |  |  | 1864 | 1942 | N/A | 
| Machiasport Railroad |  |  | 1845 | 1872 | Whitneyville and Machiasport Railroad | 
| Madrid Railroad |  | MEC | 1902 | 1908 | Sandy River and Rangeley Lakes Railroad | 
| Maine Central Railroad | MEC | MEC | 1862 |  |  | Still exists as a lessor of Pan Am Railways operating subsidiary Springfield Terminal Railway | 
| Maine Coast Railroad | MC |  | 1990 | 2000 | Safe Handling Rail, Inc. | 
| Maine, New Hampshire and Massachusetts Railroad |  | B&M | 1836 | 1844 | Boston and Maine Railroad | 
| Maine Shore Line Railroad |  | MEC | 1881 | 1888 | Maine Central Railroad | 
| Monson Railroad |  |  | 1885 | 1943 | N/A | 
| Monson and Athens Railroad |  |  | 1881 | 1885 | Monson Railroad | 
| Montreal, Maine and Atlantic Railway | MMA | MMA | 2002 | 2004 | Central Maine and Quebec Railway | Went bankrupt following the Lac-Mégantic derailment | 
| New Brunswick Railway |  | CP | 1878 | 1890 | Canadian Pacific Railway | 
| New Brunswick and Canada Railway |  | CP | 1870 | 1882 | New Brunswick Railway | 
| Northern Maine Seaport Railroad |  | BAR | 1904 | 1919 | Bangor and Aroostook Railroad | 
| Norway Branch Railroad |  | CN | 1879 |  |  | 
| Oldtown and Lincoln Railroad |  | MEC | 1852 | 1864 | European and North American Railway | 
| Orchard Beach Railroad |  | B&M | 1876 | 1893 | Boston and Maine Railroad | 
| Palmer and Machiasport Railroad |  |  | 1842 | 1845 | Machiasport Railroad | 
| Patten and Sherman Railroad |  | BAR | 1895 | 1901 | Bangor and Aroostook Railroad | 
| Penobscot Railroad |  | MEC | 1853 | 1863 | European and North American Railway | 
| Penobscot and Kennebec Railroad |  | MEC | 1845 | 1862 | Maine Central Railroad | 
| Penobscot and Lake Megantic Railroad |  | CP | 1871 | 1881 | International Railway of Maine | 
| Penobscot, Lincoln and Kennebec Railroad |  | MEC | 1849 | 1864 | Knox and Lincoln Railroad | 
| Penobscot Shore Line Railroad |  | MEC | 1889 | 1891 | Knox and Lincoln Railway | 
| Penobscot and Union River Railroad |  | MEC | 1870 | 1873 | Bucksport and Bangor Railroad | 
| Phillips and Rangeley Railroad |  | MEC | 1889 | 1908 | Sandy River and Rangeley Lakes Railroad | 
| Portland and Kennebec Railroad |  | MEC | 1862 | 1874 | Maine Central Railroad | 
| Portland and Ogdensburg Railroad |  | MEC | 1867 | 1887 | Portland and Ogdensburg Railway | 
| Portland and Ogdensburg Railway |  | MEC | 1886 | 1943 | Maine Central Railroad | 
| Portland and Oxford Central Railroad |  | MEC | 1857 | 1896 | Portland and Rumford Falls Railway | 
| Portland and Rochester Railroad |  | B&M | 1864 | 1900 | Boston and Maine Railroad | 
| Portland and Rumford Falls Railroad |  | MEC | 1907 | 1946 | Maine Central Railroad | 
| Portland and Rumford Falls Railway |  | MEC | 1890 | 1946 | Maine Central Railroad | 
| Portland, Saco and Portsmouth Railroad |  | B&M | 1837 | 1900 | Boston and Maine Railroad | 
| Portland Terminal Company | PTM | MEC | 1911 |  |  | Still exists as a lessor of Pan Am Railways operating subsidiary Springfield Terminal Railway | 
| Portland Union Railway Station Company |  | MEC | 1887 | 1911 | Portland Terminal Company | 
| Portsmouth, Great Falls and Conway Railroad |  | B&M | 1865 | 1890 | Boston and Maine Railroad | 
| Rangeley Lakes and Megantic Railroad |  | MEC | 1909 | 1914 | Maine Central Railroad | 
| Rockport Railroad |  |  | 1886 | 1896 | N/A | 
| Rumford Falls and Buckfield Railroad |  | MEC | 1874 | 1896 | Portland and Rumford Falls Railway | 
| Rumford Falls and Rangeley Lakes Railroad |  | MEC | 1894 | 1936 | N/A | 
| Safe Handling Rail, Inc. |  |  | 2000 | 2003 | Maine Eastern Railroad | 
| St. Croix and Penobscot Railroad |  | MEC | 1870 | 1899 | Washington County Railroad | 
| Sandy River Railroad |  | MEC | 1879 | 1908 | Sandy River and Rangeley Lakes Railroad | 
| Sandy River and Rangeley Lakes Railroad |  | MEC | 1908 | 1935 | N/A | 
| Sanford and Eastern Railroad |  |  | 1949 | 1961 | N/A | 
| Schoodic Stream Railroad |  | BAR | 1906 | 1907 | Bangor and Aroostook Railroad | 
| Sebasticook and Moosehead Railroad |  | MEC | 1886 | 1910 | Maine Central Railroad | 
| Somerset Railroad |  | MEC | 1860 | 1883 | Somerset Railway | 
| Somerset Railway |  | MEC | 1904 | 1911 | Maine Central Railroad | 
| Somerset Railway |  | MEC | 1883 | 1904 | Kennebec Valley Railroad | 
| Somerset and Kennebec Railroad |  | MEC | 1848 | 1874 | Maine Central Railroad | 
| Van Buren Bridge Company | VB | BAR | 1913 | 2003 | Montreal, Maine and Atlantic Railway | 
| Washington County Railroad |  | MEC | 1893 | 1903 | Washington County Railway | 
| Washington County Railway |  | MEC | 1903 | 1911 | Maine Central Railroad | 
| Waterville and Wiscasset Railroad |  |  | 1895 | 1901 | Wiscasset, Waterville and Farmington Railroad | 
| Whitneyville and Machiasport Railroad |  |  | 1872 | 1892 | N/A | 
| Wiscasset and Moosehead Lake Railroad |  |  | 1873 | 1876 | Wiscasset and Quebec Railroad | 
| Wiscasset and Quebec Railroad |  |  | 1876 | 1901 | Wiscasset, Waterville and Farmington Railroad | 
| Wiscasset, Waterville and Farmington Railroad |  |  | 1901 | 1906 | Wiscasset, Waterville and Farmington Railway | 
| Wiscasset, Waterville and Farmington Railway |  |  | 1907 | 1933 | N/A | 
| York and Cumberland Railroad |  | B&M | 1846 | 1865 | Portland and Rochester Railroad | 
| York Harbor and Beach Railroad |  | B&M | 1883 | 1927 | N/A |