| Name | Mark | System | From | To | Successor | Notes |
| Albany and Lebanon Railroad | | SP | 1880 | 1881 | Oregon and California Railroad | - |
| Astoria and Columbia River Railroad | | GN/ NP | 1895 | 1911 | Spokane, Portland and Seattle Railway | - |
| Astoria and South Coast Railway | | GN/ NP | 1888 | 1892 | Seashore Road Company | - |
| Astoria Southern Railway | | | 1910 | 1943 | N/A | - |
| Beaverton and Willsburg Railroad | | SP | 1906 | 1916 | Southern Pacific Company | - |
| Boise and Western Railway | | UP | 1909 | 1910 | Oregon Eastern Railway | - |
| Burlington Northern Inc. | BN | | 1970 | 1981 | Burlington Northern Railroad | - |
| Burlington Northern Railroad | BN | | 1981 | 1996 | Burlington Northern and Santa Fe Railway | - |
| Burlington Northern (Oregon–Washington), Inc. | | | 1981 | 1985 | Burlington Northern Railroad | - |
| California Northeastern Railway | | SP | 1905 | 1911 | Oregon Eastern Railway | - |
| California and Oregon Coast Railroad | | | 1913 | 1954 | N/A | - |
| Carlton and Coast Railroad | CR&C | | 1910 | 1940 | N/A | - |
| Central Railroad of Oregon | | | 1909 | 1927 | Union Railroad of Oregon | - |
| Central Railway of Oregon | | | 1905 | 1909 | Central Railroad of Oregon | - |
| Central Oregon Railroad | | GN/ NP | 1908 | 1909 | Oregon Trunk Railway | - |
| Central Pacific Railway | | SP | 1912 | 1959 | Southern Pacific Company | - |
| Clackamas Southern Railway | | | 1908 | 1914 | Willamette Valley Southern Railway | - |
| Columbia and Nehalem River Railroad | | | 1913 | 1925 | N/A | - |
| Columbia River and Astoria Railway | | GN/ NP | 1891 | 1895 | Astoria and Columbia River Railroad | - |
| Columbia River and Oregon Central Railroad | | UP | 1903 | 1910 | Oregon Railroad and Navigation Company | - |
| Columbia Southern Railway | | UP | 1897 | 1910 | Oregon Railroad and Navigation Company | - |
| Condon, Kinzua and Southern Railroad | CKSO | | 1928 | 1976 | N/A | - |
| Coos Bay, Roseburg and Eastern Railroad and Navigation Company | | SP | 1890 | 1915 | Southern Pacific Company | - |
| Corvallis and Alsea River Railway | | SP | 1907 | 1911 | Portland, Eugene and Eastern Railway | - |
| Corvallis and Eastern Railroad | | SP | 1897 | 1915 | Southern Pacific Company | - |
| Corvallis and Yaquina Bay Railroad | | | 1872 | 1874 | Willamette Valley and Coast Railroad | - |
| The Dalles and Southern Railroad | | | 1933 | 1936 | N/A | - |
| Dayton, Sheridan and Grande Ronde Railroad | | SP | 1877 | 1879 | Willamette Valley Railroad | - |
| Des Chutes Railroad | | UP | 1906 | 1987 | Union Pacific Railroad | - |
| East Portland Traction Company | EPTC | | 1987 | 1997 | Oregon Pacific Railroad | - |
| Gales Creek and Wilson River Railroad | | GN/ NP | 1917 | 1944 | Spokane, Portland and Seattle Railway | - |
| Goble, Nehalem and Pacific Railway | | | 1902 | 1922 | N/A | - |
| Great Northern Railway | GN | GN | 1927 | 1970 | Burlington Northern Inc. | - |
| Great Southern Railroad | | | 1904 | 1933 | The Dalles and Southern Railroad | - |
| Great Western Railway of Colorado | GWR | | 1986 | 1987 | Great Western Railway of Oregon | - |
| Great Western Railway of Oregon | GWR | | 1987 | 1997 | Lake County Railroad | - |
| Independence and Monmouth Railway | | SP | 1889 | 1918 | N/A | - |
| Klamath Lake Railroad | | | 1901 | 1913 | N/A | - |
| Lake County Railroad | LCR | | 1997 | 2005 | Modoc Northern Railroad | - |
| Longview, Portland and Northern Railway | LPN | | 1952 | 1999 | N/A | - |
| LRY LLC (DBA Lake Railway) | LRY | | 2009 | 2017 | Goose Lake Railway LLC | - |
| Malheur Railroad | | | 1923 | 1928 | Oregon and Northwestern Railroad | - |
| Malheur Valley Railway | | UP | 1906 | 1910 | Oregon–Washington Railroad and Navigation Company | - |
| Marion and Linn County Railroad | | SP | 1918 | 1927 | Southern Pacific Company | - |
| Medford and Crater Lake Railroad | | GN/ NP | 1904 | 1907 | Pacific and Eastern Railway | - |
| Modoc Northern Railroad | MNRR | | 2005 | 2009 | LRY LLC (DBA Lake Railway) | - |
| Molalla Western Railway | MWRL | | 1993 | 1997 | Oregon Pacific Railroad | - |
| Mount Hood Railroad | | UP | 1905 | 1968 | Mount Hood Railway | - |
| Mount Hood Railway | MH | UP | 1968 | 1987 | Mount Hood Railroad | - |
| Nevada–California–Oregon Railway | | SP | 1888 | 1945 | Central Pacific Railway | - |
| Northern Pacific Railroad | | NP | 1864 | 1896 | Northern Pacific Railway | - |
| Northern Pacific Railway | NP | NP | 1896 | 1970 | Burlington Northern Inc. | - |
| Northern Pacific Terminal Company of Oregon | | NP/ SP/ UP | 1882 | 1965 | Portland Terminal Railroad | - |
| Northwest Railway | | UP | | | Northwestern Railroad | - |
| Northwestern Railroad | | UP | 1906 | 1910 | Oregon–Washington Railroad and Navigation Company | - |
| Oregon Railway | | SP | 1880 | 1880 | Oregonian Railway | - |
| Oregon Railroad and Navigation Company | | UP | 1896 | 1910 | Oregon–Washington Railroad and Navigation Company | - |
| Oregon Railway Extensions Company | | UP | 1888 | 1896 | Oregon Railroad and Navigation Company | - |
| Oregon Railway and Navigation Company | | UP | 1879 | 1896 | Oregon Railroad and Navigation Company | - |
| Oregon and California Railroad | | SP | 1870 | 1927 | Southern Pacific Company | - |
| Oregon, California and Eastern Railway | OCE | GN/ SP | 1915 | 1990 | N/A | - |
| Oregon Central Railroad | | SP | 1866 | 1880 | Oregon and California Railroad | - |
| Oregon Central Rail Road | | SP | 1867 | 1870 | Oregon and California Railroad | - |
| Oregon Central and Eastern Railroad | | SP | 1895 | 1898 | Corvallis and Eastern Railroad | - |
| Oregon Eastern Railway | | SP, UP | 1905 | 1912 | Central Pacific Railway, Oregon–Washington Railroad and Navigation Company | - |
| Oregon [Electric Railway] | OE | GN/ NP | 1906 | 1981 | Burlington Northern (Oregon–Washington), Inc. | Electric until 1945 |
| Oregon and Northwestern Railroad | ONW | | 1934 | 1984 | N/A | - |
| Oregon Pacific Railroad | | SP | 1880 | 1894 | Oregon Central and Eastern Railroad | - |
| Oregon, Pacific and Eastern Railway | OPE | | 1912 | 1994 | N/A | - |
| Oregon Short Line Railroad | | UP | 1897 | 1987 | Union Pacific Railroad | - |
| Oregon Short Line Railway | | UP | 1882 | 1889 | Oregon Short Line and Utah Northern Railway | - |
| Oregon Short Line and Utah Northern Railway | | UP | 1889 | 1897 | Oregon Short Line Railroad | - |
| Oregon and Southeastern Railroad | | | 1905 | 1914 | Oregon, Pacific and Eastern Railway | - |
| Oregon Southern Railway | | UP | | | Columbia River and Oregon Central Railroad | - |
| Oregon Portage Railroad | | | 1858 | 1896 | N/A | - |
| Oregon Steam Navigation Company | | UP | 1862 | 1880 | Oregon Railway and Navigation Company | - |
| Oregon Trunk Railway | OT | GN/ NP | 1909 | 1981 | Burlington Northern (Oregon–Washington), Inc. | - |
| Oregon Trunk Line, Inc. | | GN/ NP | 1906 | 1909 | Oregon Trunk Railway | - |
| Oregon and Washington Railroad | | UP | 1906 | 1910 | Oregon–Washington Railroad and Navigation Company | - |
| Oregon–Washington Railroad and Navigation Company | | UP | 1910 | 1987 | Union Pacific Railroad | - |
| Oregon and Washington Territory Railroad | | NP | 1886 | 1892 | Washington and Columbia River Railway | - |
| Oregon Western Railroad | | SP | 1889 | 1890 | Oregonian Railroad | - |
| Oregon Western Railway | | SP | 1905 | 1914 | Willamette Pacific Railroad Company | - |
| Oregonian Railroad | | SP | 1890 | 1893 | Oregon and California Railroad | - |
| Oregonian Railway | | SP | 1880 | 1889 | Oregon Western Railroad | - |
| Pacific Railway and Navigation Company | | SP | 1905 | 1915 | Southern Pacific Company | - |
| Pacific Coast Line Railway | | SP | 1911 | 1912 | Willamette Pacific Railroad Company | - |
| Pacific and Eastern Railway | | GN/ NP | 1907 | 1919 | N/A | - |
| Pacific Great Western Railway | | SP | 1911 | 1912 | Willamette Pacific Railroad Company | - |
| Portland, Astoria and Pacific Railroad | | GN/ NP | 1919 | 1921 | United Railways | - |
| Portland, Eugene and Eastern Railway | | SP | 1907 | 1915 | Southern Pacific Company | - |
| Portland and Southwestern Railroad | | | 1905 | 1944 | N/A | - |
| Portland Terminal Railroad | PTRC | NP/ SP/ UP | 1965 | | | Still exists as a joint subsidiary of the BNSF Railway and Union Pacific Railroad |
| Portland Traction Company | PRTD | SP/ UP | 1930 | 1991 | East Portland Traction Company | Electric until 1958 |
| Portland and Willamette Valley Railway | | SP | 1885 | 1892 | Portland and Yamhill Railroad | - |
| Portland and Yamhill Railroad | | SP | 1892 | 1893 | Oregon and California Railroad | - |
| Rogue River Valley Railway | | | 1891 | 1915 | Southern Oregon Traction Company | - |
| Salem, Falls City and Western Railway | | SP | 1901 | 1915 | Southern Pacific Company | - |
| Seashore Road Company | | GN/ NP | 1893 | 1897 | Astoria and Columbia River Railroad | - |
| Sheridan and Willamina Railroad | | SP | 1907 | 1913 | Portland, Eugene and Eastern Railway | - |
| Southern Extensions Railway | | UP | 1906 | | Des Chutes Railroad | - |
| Southern Pacific Company | SP | SP | 1887 | 1969 | Southern Pacific Transportation Company | - |
| Southern Pacific Transportation Company | SP | SP | 1969 | 1998 | Union Pacific Railroad | - |
| Spokane, Portland and Seattle Railway | SP&S, SPS | GN/ NP | 1908 | 1979 | Burlington Northern Inc. | - |
| Sumpter Valley Railway | | | 1890 | 1961 | N/A | - |
| Terminal Railway | | SP | 1911 | 1913 | Willamette Pacific Railroad | - |
| Umatilla Central Railroad | | UP | 1906 | 1910 | Oregon–Washington Railroad and Navigation Company | - |
| Union Railroad of Oregon | UO | | 1927 | 1993 | N/A | - |
| Union Railway | | | 1890 | 1894 | Union Street and Suburban Railway | - |
| Union, Cove and Valley Railway | | | 1905 | 1906 | Central Railway of Oregon | - |
| Union Street and Suburban Railway | | | 1894 | 1906 | Union, Cove and Valley Railway | - |
| United Railways | URC | GN/ NP | 1906 | 1944 | Spokane, Portland and Seattle Railway | - |
| Valley and Siletz Railroad | VS | | 1912 | 1985 | Willamette Valley Railroad | - |
| Walla Walla and Columbia River Railroad | | UP | 1868 | 1910 | Oregon Railroad and Navigation Company | - |
| Walla Walla Valley Railway | WWV | NP | 1910 | 1985 | N/A | Electric until 1949 |
| Washington and Columbia River Railway | | NP | 1892 | 1907 | Northern Pacific Railway | - |
| Western Oregon Railroad | | SP | 1879 | 1880 | Oregon and California Railroad | - |
| WCTU Railway LLC | | | 1975 | 2013 | Rogue Valley Terminal Railroad Corporation | - |
| White City Terminal & Utilities Co. | | | 1954 | 1974 | WCTU Railway LLC | - |
| Willamette Pacific Railroad Company | | SP | 1911 | 1915 | Southern Pacific Company | - |
| Willamette Valley Railroad | WVRD | | 1984 | 1994 | Willamina and Grand Ronde Railway | - |
| Willamette Valley Railroad | | SP | 1878 | 1880 | Oregon Railway | - |
| Willamette Valley and Coast Railroad | | | 1911 | | N/A | - |
| Willamette Valley and Coast Railroad | | SP | 1874 | 1894 | Oregon Central and Eastern Railroad | - |
| Willamina and Grand Ronde Railroad | WGRR | | 1980 | 1986 | Willamette Valley Railroad | - |
| Willamina and Grand Ronde Railway | WGR | | 1988 | 1996 | Willamette Valley Railway | - |
| Willamina and Grand Ronde Railway | | | 1920 | 1955 | Longview, Portland and Northern Railway | - |