| Name | Mark | System | From | To | Successor | Notes |
| Alabama and Chattanooga Railroad | | SOU | 1868 | 1877 | Alabama Great Southern Railroad | - |
| Arkansas and Memphis Railway Bridge and Terminal Company | | MP/ RI/ SSW | 1912 | | | Still exists as a nonoperating subsidiary of the Union Pacific Railroad |
| Athens and Tellico Railway | | L&N | 1910 | 1911 | Louisville and Nashville Railroad | - |
| Atlanta, Knoxville and Northern Railway | | L&N | 1896 | 1905 | Louisville and Nashville Railroad | - |
| Atlantic, Tennessee and Ohio Railroad | | SOU | 1852 | 1894 | N/A | Sold at foreclosure; no property in Tennessee |
| Beaver Dam Railroad | | | 1900 | 1918 | N/A | - |
| Belt Railway of Chattanooga | | SOU | 1895 | 1946 | Alabama Great Southern Railroad | - |
| Birmingham and Northwestern Railway | | GM&O | 1910 | 1929 | Gulf, Mobile and Northern Railroad | - |
| Bon Air Railway | | L&N | 1887 | 1887 | Nashville, Chattanooga and St. Louis Railway | - |
| Brimstone Railroad | | SOU | 1941 | 1965 | Brimstone and New River Railway | - |
| Brimstone and New River Railway | | SOU | 1965 | 1966 | New River Railway | - |
| Bristol, Elizabethtown and North Carolina Railway | | SOU | 1889 | 1895 | Virginia and Southwestern Railway | - |
| Burlington Northern Inc. | BN | | 1980 | 1981 | Burlington Northern Railroad | - |
| Burlington Northern Railroad | BN | | 1981 | 1996 | Burlington Northern and Santa Fe Railway | - |
| Cambria Southern Railway | | L&N | 1904 | 1904 | Atlanta, Knoxville and Northern Railway | - |
| Carolina, Clinchfield and Ohio Railway | CC&O | ACL/ L&N | 1908 | 1990 | CSX Transportation | - |
| Carolina, Cumberland Gap and Chicago Railway | | SOU | 1882 | 1895 | N/A | Sold at foreclosure; no property in Tennessee |
| Central of Georgia Railway | CG | CG | 1901 | 1971 | Central of Georgia Railroad | - |
| Central Mississippi Railroad | | IC | 1877 | 1878 | Chicago, St. Louis and New Orleans Railroad | - |
| Central Southern Railroad | | L&N | 1853 | 1866 | Nashville and Decatur Railroad | - |
| Central of Tennessee Railway and Navigation Company | CTRN | | 1992 | 2000 | Nashville and Western Railroad | - |
| Charleston, Cincinnati and Chicago Railroad | | ACL/ L&N | 1887 | 1893 | Ohio River and Charleston Railway | - |
| Chattanooga Railway, Bridge and Terminal Company | | SOU | 1890 | 1892 | Chattanooga Terminal Railway | - |
| Chattanooga, Harrison and Cleveland Railroad | | SOU | 1850 | 1852 | Chattanooga, Harrison, Georgetown and Charleston Railroad | - |
| Chattanooga, Harrison, Georgetown and Charleston Railroad | | SOU | 1852 | 1854 | East Tennessee and Georgia Railroad | - |
| Chattanooga, Rome and Columbus Railroad | | CG | 1887 | 1891 | Savannah and Western Railroad | - |
| Chattanooga, Rome and Southern Railroad | | CG | 1897 | 1901 | Central of Georgia Railway | - |
| Chattanooga Southern Railroad | | SOU | 1896 | 1911 | Tennessee, Alabama and Georgia Railroad | - |
| Chattanooga Southern Railway | | SOU | 1894 | 1895 | Chattanooga Southern Railroad | - |
| Chattanooga Station Company | | CG/ SOU | 1905 | | | - |
| Chattanooga Terminal Railway | | SOU | 1892 | 1993 | Alabama Great Southern Railroad | - |
| Chattanooga Union Railway | | SOU | 1888 | 1895 | Belt Railway of Chattanooga | - |
| Chattanooga and Lookout Mountain Railway | | | 1889 | 1928 | N/A | - |
| Chesapeake and Nashville Railway | | L&N | 1884 | 1892 | Gallatin and Scottsville Railway | - |
| Chesapeake, Ohio and Southwestern Railroad | | IC | 1881 | 1896 | Chicago, St. Louis and New Orleans Railroad | - |
| Chicago, Memphis and Gulf Railroad | | IC | 1909 | 1963 | Illinois Central Railroad | - |
| Chicago, Rock Island and Pacific Railroad | RI, ROCK | RI | 1948 | 1980 | N/A | - |
| Chicago, Rock Island and Pacific Railway | RI | RI | | 1948 | Chicago, Rock Island and Pacific Railroad | - |
| Chicago, St. Louis and New Orleans Railroad | | IC | 1878 | 1951 | Illinois Central Railroad | - |
| Cincinnati and Charleston Railroad | | SOU | 1836 | 1837 | Louisville, Cincinnati and Charleston Railroad | - |
| Cincinnati, Cumberland Gap and Charleston Railroad | | SOU | 1853 | 1871 | East Tennessee, Virginia and Georgia Railroad | - |
| Cincinnati, Green River and Nashville Railroad | | L&N | 1882 | 1884 | Chesapeake and Nashville Railway | - |
| Cincinnati, Nashville, Southern Railway | | | 1912 | 1934 | N/A | - |
| Cincinnati Southern Railway | | SOU | 1870 | | | Still exists as a lessor of Norfolk Southern Railway operating subsidiary Cincinnati, New Orleans and Texas Pacific Railway |
| Clinchfield Railroad | CRR | ACL/ L&N | 1924 | 1983 | Seaboard System Railroad | - |
| Coal Creek and New River Railroad | | SOU | 1877 | 1889 | Knoxville and Ohio Railroad | - |
| Corinth and Counce Railroad | CCR | | 1958 | 1991 | TennRail Corporation | - |
| Crandull and Shady Valley Railway | | | 1909 | 1918 | N/A | - |
| Cumberland Railway | | SOU | 1902 | 1944 | Southern Railway | - |
| Cumberland and Big Stone Gaps Railroad | | L&N | 1889 | 1900 | Louisville and Nashville Railroad | - |
| Cumberland Plateau Railroad | | TC | 1901 | 1902 | Tennessee Central Railroad | - |
| Decatur, Chesapeake and New Orleans Railway | | L&N | 1887 | 1893 | Middle Tennessee and Alabama Railway | - |
| Duck River Valley Narrow Gauge Railroad | | L&N | 1872 | 1879 | Nashville, Chattanooga and St. Louis Railway | - |
| Dyersburg Northern Railroad | | IC | 1904 | 1909 | Chicago, Memphis and Gulf Railroad | - |
| East Tennessee and Georgia Railroad | | SOU | 1848 | 1869 | East Tennessee, Virginia and Georgia Railroad | - |
| East Tennessee and Virginia Railroad | | SOU | 1848 | 1869 | East Tennessee, Virginia and Georgia Railroad | - |
| East Tennessee, Virginia and Georgia Railroad | | SOU | 1869 | 1886 | East Tennessee, Virginia and Georgia Railway | - |
| East Tennessee, Virginia and Georgia Railway | | SOU | 1886 | 1894 | Southern Railway | - |
| East Tennessee and Western North Carolina Railroad | ETWN | | 1866 | 1983 | East Tennessee Railway | - |
| Edgefield and Kentucky Railroad | | L&N | 1852 | 1872 | Nashville, Chicago and St. Louis Railroad | - |
| Emory River Railroad | | | 1918 | 1958 | | formerly the Emory River Lumber Company until 1943 |
| Gallatin and Scottsville Railway | | L&N | 1906 | 1907 | Louisville and Nashville Railroad | - |
| Greenback Railroad | | L&N | 1905 | 1907 | Louisville and Nashville Railroad | - |
| Gulf and Chicago Railroad | | GM&O | 1889 | 1903 | Gulf and Chicago Railway | - |
| Gulf and Chicago Railway | | GM&O | 1903 | 1909 | New Orleans, Mobile and Chicago Railroad | - |
| Gulf and Mississippi Railroad | GMSR | | 1985 | 1988 | SouthRail Corporation | - |
| Gulf, Mobile and Northern Railroad | GM&N | GM&O | 1915 | 1940 | Gulf, Mobile and Ohio Railroad | - |
| Gulf, Mobile and Ohio Railroad | GM&O | GM&O | 1940 | 1972 | Illinois Central Gulf Railroad | - |
| Harriman Railway and Construction Company | | SOU | 1890 | 1891 | Harriman Coal and Iron Railroad | - |
| Harriman Coal and Iron Railroad | | SOU | 1891 | 1895 | Harriman and Northeastern Railroad | - |
| Harriman, Knoxville and Eastern Railroad | | L&N | 1910 | 1913 | Louisville and Nashville Railroad | - |
| Harriman and Northeastern Railroad | | SOU | 1895 | 1970 | Cincinnati, New Orleans and Texas Pacific Railway | - |
| Henderson and Nashville Railroad | | L&N | 1848 | 1867 | N/A | Sold at foreclosure; no property in Tennessee |
| Hickman and Obion Railroad | | L&N | 1853 | 1855 | Nashville and Northwestern Railroad | sold to Nashville and Chattanooga Railroad in 1872 |
| Hiwassee Railroad | | SOU | 1836 | 1848 | East Tennessee and Georgia Railroad | - |
| Holston River Railway | | SOU | 1905 | 1908 | Virginia and Southwestern Railway | - |
| Holston Valley Railway | | | 1892 | 1915 | Bristol Traction Company | - |
| Illinois Central Railroad | IC | IC | 1883 | 1972 | Illinois Central Gulf Railroad | - |
| Illinois Central Gulf Railroad | ICG | | 1972 | 1988 | Illinois Central Railroad | - |
| Indiana, Alabama and Texas Railroad | | L&N | 1885 | 1887 | Louisville and Nashville Railroad | - |
| Iron Mountain Railroad of Memphis | | MP | 1886 | 1966 | Missouri Pacific Railroad | - |
| Jackson and Southeastern Railroad | | IC | 1905 | 1913 | Chicago, St. Louis and New Orleans Railroad | - |
| Jamestown Railroad | | | 1912 | 1913 | Oneida and Western Railroad | - |
| Johnson City, Bakersville and Southern Railway | | | 1905 | 1909 | Unicoi Railway | - |
| Johnson City and Carolina Railway | | SOU | 1887 | 1891 | East Tennessee, Virginia and Georgia Railway | - |
| Kansas City, Fort Scott and Memphis Railroad | | SLSF | | 1901 | St. Louis and San Francisco Railroad | - |
| Kansas City and Memphis Railway and Bridge Company | | SLSF | 1887 | 1928 | St. Louis – San Francisco Railway | - |
| Kansas City, Memphis and Birmingham Railroad | | SLSF | 1886 | 1928 | St. Louis – San Francisco Railway | - |
| Kingsport Southern Railway | | ACL/ L&N | 1906 | 1906 | South and Western Railroad | - |
| Knoxville and Augusta Railroad | | SOU | 1878 | 1890 | East Tennessee, Virginia and Georgia Railway | - |
| Knoxville Belt Railroad | | SOU | 1887 | 1898 | Southern Railway | - |
| Knoxville and Bristol Railway | | SOU | 1898 | 1903 | Southern Railway | - |
| Knoxville and Carolina Railroad | | | 1921 | 1926 | Smoky Mountain Railroad | - |
| Knoxville and Charleston Railroad | | SOU | 1852 | 1873 | Knoxville and Augusta Railroad | - |
| Knoxville, Cumberland Gap and Louisville Railroad | | SOU | 1888 | 1895 | Knoxville, Cumberland Gap and Louisville Railway | - |
| Knoxville, Cumberland Gap and Louisville Railway | | SOU | 1895 | 1898 | Southern Railway | - |
| Knoxville and Kentucky Railroad | | SOU | 1853 | 1871 | Coal Creek and New River Railroad | - |
| Knoxville, La Follette and Jellico Railroad | | L&N | 1902 | 1904 | Louisville and Nashville Railroad | - |
| Knoxville and Ohio Railroad | | SOU | 1871 | 1903 | Southern Railway | - |
| Knoxville, Sevierville and Eastern Railway | | | 1907 | 1921 | Knoxville and Carolina Railroad | - |
| Knoxville Southern Railroad | | L&N | 1887 | 1890 | Marietta and North Georgia Railway | - |
| La Grange and Memphis Railroad | | SOU | 1835 | 1852 | Memphis and Charleston Railroad | - |
| Laurel Railway | | | 1905 | 1926 | N/A | - |
| Laurel Fork Railway | | | 1910 | 1925 | N/A | - |
| Lewisburg and Northern Railroad | | L&N | 1910 | 1915 | Louisville and Nashville Railroad | - |
| Lexington and Knoxville Railroad | | SOU | 1852 | 1853 | Knoxville and Kentucky Railroad | - |
| Little River Railroad | LR | | 1901 | 1940 | N/A | - |
| Livingston Terminal Company | | | 1910 | 1911 | Overton County Railroad | - |
| Louisville, Cincinnati and Charleston Railroad | | SOU | 1837 | 1843 | N/A | Sold at foreclosure; no property in Tennessee |
| Louisville and Nashville Railroad | L&N, LN | L&N | 1851 | 1983 | Seaboard System Railroad | - |
| Louisville and Nashville Terminal Company | | L&N | 1893 | 1962 | Louisville and Nashville Railroad | - |
| Louisville, New Orleans and Texas Railway | | IC | 1884 | 1892 | Yazoo and Mississippi Valley Railroad | - |
| Marietta and North Georgia Railway | | L&N | 1890 | 1895 | Atlanta, Knoxville and Northern Railway | - |
| McCormick, Ashland City and Nashville Railroad | MACO | | 1988 | 1992 | Central of Tennessee Railway and Navigation Company | - |
| McMinnville and Manchester Railroad | | L&N | 1850 | 1875 | Memphis and Charleston Railroad | sold to Nashville, Chattanooga and St. Louis Railway in 1877 |
| Memphis, Birmingham and Atlantic Railroad | | SLSF | 1885 | 1887 | Kansas City, Memphis and Birmingham Railroad | - |
| Memphis and Charleston Railroad | | SOU | 1846 | 1898 | Southern Railway | - |
| Memphis–Chattanooga Railway | | SOU | 1899 | 1941 | Southern Railway | - |
| Memphis, Clarksville and Louisville Railroad | | L&N | 1852 | 1871 | Louisville and Nashville Railroad | - |
| Memphis, Holly Springs and Mobile Railroad | | SLSF | 1860 | 1869 | Memphis, Holly Springs, Okolona and Selma Railroad | - |
| Memphis, Holly Springs, Okolona and Selma Railroad | | SLSF | 1869 | 1870 | Selma, Marion and Memphis Railroad | - |
| Memphis, Holly Springs and Selma Railroad | | SLSF | 1881 | 1881 | Memphis, Selma and Brunswick Railroad | - |
| Memphis and Ohio Railroad | | L&N | 1853 | 1872 | Louisville and Nashville Railroad | - |
| Memphis, Paducah and Northern Railroad | | IC | 1878 | 1881 | Chesapeake, Ohio and Southwestern Railroad | - |
| Memphis, Selma and Brunswick Railroad | | SLSF | 1881 | 1885 | Memphis, Birmingham and Atlantic Railroad | - |
| Memphis and Southeastern Railroad | | SLSF | 1886 | 1886 | Kansas City, Memphis and Birmingham Railroad | - |
| Memphis and State Line Railroad | | IC | 1903 | 1908 | Chicago, St. Louis and New Orleans Railroad | - |
| Memphis Union Station Company | MUSC | L&N/ MP/ SOU/ SSW | 1909 | 1976 | N/A | - |
| Mentor Southern Railway | | L&N | 1904 | 1904 | Atlanta, Knoxville and Northern Railway | - |
| Middle and East Tennessee Central Railway | | L&N | 1883 | 1897 | Gallatin and Scottsville Railway | - |
| Middle Tennessee Railroad | | | 1907 | 1920 | N/A | - |
| Middle Tennessee and Alabama Railway | | L&N | 1893 | 1897 | Nashville, Chattanooga and St. Louis Railway | - |
| Middlesborough Railroad | | L&N | 1895 | 1896 | Louisville and Nashville Railroad | - |
| Middlesborough Belt Railroad | | L&N | 1890 | 1895 | Middlesborough Railroad | - |
| Mississippi Central Railroad | | IC | 1859 | 1874 | New Orleans, St. Louis and Chicago Railroad | - |
| Mississippi Central and Tennessee Railroad | | IC | 1853 | 1859 | Mississippi Central Railroad | - |
| Mississippi River Railway | | IC | 1858 | 1872 | Paducah and Memphis Railroad | - |
| Mississippi and Tennessee RailNet | MT | | 1998 | 2003 | Mississippi Tennessee Railroad | - |
| Mississippi Tennessee Railroad | MTNR | | 2003 | 2004 | N/A | - |
| Mississippi and Tennessee Railroad | | IC | 1853 | 1889 | Chicago, St. Louis and New Orleans Railroad | - |
| Missouri Pacific Railroad | MP | MP | 1917 | 1997 | Union Pacific Railroad | - |
| Mobile, Clarksville and Evansville Railroad | | L&N | 1881 | 1885 | Indiana, Alabama and Texas Railroad | - |
| Mobile, Jackson and Kansas City Railroad | | GM&O | 1903 | 1909 | New Orleans, Mobile and Chicago Railroad | - |
| Mobile and Ohio Railroad | | GM&O | 1848 | 1940 | Gulf, Mobile and Ohio Railroad | - |
| Morgan and Fentress Railway | | | 1914 | 1934 | N/A | - |
| Morristown and Carolina Railroad | | SOU | 1881 | 1882 | Carolina, Cumberland Gap and Chicago Railway | - |
| Morristown and Cumberland Railroad | | SOU | 1890 | 1898 | Knoxville and Bristol Railway | - |
| Morristown, Cumberland Gap and Ohio Railroad | | SOU | 1880 | 1882 | Carolina, Cumberland Gap and Chicago Railway | - |
| Nashville and Ashland City Railroad | NACR | | 1981 | 1988 | McCormick, Ashland City and Nashville Railroad | - |
| Nashville and Atlantic Railroad | | | 1921 | 1939 | N/A | - |
| Nashville and Chattanooga Railroad | | L&N | 1845 | 1873 | Nashville, Chattanooga and St. Louis Railway | changed name |
| Nashville, Chattanooga and St. Louis Railway | N&C, NC | L&N | 1873 | 1957 | Louisville and Nashville Railroad | - |
| Nashville, Chicago and St. Louis Railroad | | L&N | 1872 | 1872 | St. Louis and South Eastern Railway | - |
| Nashville and Clarksville Railroad | | TC | 1901 | 1902 | Tennessee Central Railroad | - |
| Nashville and Decatur Railroad | | L&N | 1866 | 1990 | CSX Transportation | - |
| Nashville and Florence Railroad | | L&N | 1879 | 1887 | Nashville, Florence and Sheffield Railway | - |
| Nashville, Florence and Sheffield Railway | | L&N | 1887 | 1900 | Louisville and Nashville Railroad | - |
| Nashville and Knoxville Railroad | | TC | 1884 | 1902 | Tennessee Central Railroad | - |
| Nashville and Memphis Railroad | | L&N | 1852 | 1853 | Memphis and Ohio Railroad | - |
| Nashville and Northwestern Railroad | | L&N | 1850 | 1872 | Nashville and Chattanooga Railroad | - |
| Nashville and Tellico Railroad | | L&N | 1887 | 1893 | Nashville, Tellico and Charleston Railway | - |
| Nashville, Tellico and Charleston Railway | | L&N | 1892 | 1899 | Tellico Railway | - |
| Nashville Terminal Company | | TC | 1894 | 1937 | Tennessee Central Railway | - |
| Nashville and Tuscaloosa Railroad | | L&N | 1877 | 1884 | Nashville, Chattanooga and St. Louis Railway | - |
| Natchez Trace Railroad | NTR | | 1982 | 1993 | Mississippi Central Railroad | - |
| New Orleans, Jackson and Great Northern Railroad | | IC | 1852 | 1874 | New Orleans, St. Louis and Chicago Railroad | - |
| New Orleans, Mobile and Chattanooga Railroad | | L&N | 1867 | 1871 | New Orleans, Mobile and Texas Railroad | - |
| New Orleans, Mobile and Chicago Railroad | | GM&O | 1909 | 1915 | Gulf, Mobile and Northern Railroad | - |
| New Orleans, Mobile and Texas Railroad | | L&N | 1871 | 1880 | N/A | Sold at foreclosure; no property in Tennessee |
| New Orleans and Ohio Railroad | | IC | 1866 | 1871 | Paducah and Memphis Railroad | - |
| New Orleans, St. Louis and Chicago Railroad | | IC | 1874 | 1877 | Central Mississippi Railroad | - |
| New River Railway | | SOU | 1966 | 1970 | Cincinnati, New Orleans and Texas Pacific Railway | - |
| Oakdale and Cumberland Mountain Railroad | | SOU | 1879 | 1882 | Walden's Ridge Railroad | - |
| Ohio River and Charleston Railway | | ACL/ L&N | 1894 | 1902 | South and Western Railway | - |
| Oneida and Western Railroad | OD&W | | 1913 | 1954 | N/A | - |
| Ooltewah and Red Clay Railroad | | SOU | 1881 | 1882 | Tennessee State Line Railroad | - |
| Overton County Railroad | | | 1904 | 1912 | Cincinnati, Nashville, Southern Railway | - |
| Paducah and Memphis Railroad | | IC | 1872 | 1877 | Memphis, Paducah and Northern Railroad | - |
| Paducah and Tennessee Railroad | | L&N | 1854 | 1889 | Paducah, Tennessee and Alabama Railroad | - |
| Paducah and Tennessee Railway | | L&N | 1888 | 1889 | Paducah, Tennessee and Alabama Railroad | - |
| Paducah, Tennessee and Alabama Railroad | | L&N | 1890 | 1895 | Louisville and Nashville Railroad | - |
| Powells Valley Railroad | | SOU | 1887 | 1888 | Knoxville, Cumberland Gap and Louisville Railroad | - |
| Powells Valley Railway | | SOU | 1886 | 1887 | Powells Valley Railroad | - |
| Ripley Railroad | | GM&O | 1871 | 1872 | Ship Island, Ripley and Kentucky Railroad | - |
| Rock Island Memphis Terminal Railway | | RI | 1913 | 1948 | Chicago, Rock Island and Pacific Railroad | - |
| Rockwood and Tennessee River Railway | | | 1867 | 1911 | N/A | - |
| Rogersville and Jefferson Railroad | | SOU | 1852 | 1873 | East Tennessee, Virginia and Georgia Railway | - |
| St. Louis, Iron Mountain and Southern Railway | | MP | | 1917 | Missouri Pacific Railroad | - |
| St. Louis and San Francisco Railroad | | SLSF | 1901 | 1916 | St. Louis – San Francisco Railway | - |
| St. Louis – San Francisco Railway | SLSF | SLSF | 1916 | 1980 | Burlington Northern Inc. | - |
| St. Louis and South Eastern Railway | | L&N | 1872 | 1879 | Louisville and Nashville Railroad | - |
| St. Louis Southwestern Railway | SSW | SSW | 1912 | 1997 | Union Pacific Railroad | - |
| Savannah and Western Railroad | | CG | 1891 | 1894 | Chattanooga, Rome and Southern Railroad | - |
| Seaboard System Railroad | SBD | | 1983 | 1986 | CSX Transportation | - |
| Selma, Marion and Memphis Railroad | | SLSF | 1870 | 1881 | Memphis, Holly Springs and Selma Railroad | - |
| Sequatchie Valley Railroad | | L&N | 1868 | 1877 | Nashville, Chattanooga and St. Louis Railway | - |
| Ship Island, Ripley and Kentucky Railroad | | GM&O | 1872 | 1889 | Gulf and Chicago Railroad | - |
| Smoky Mountain Railroad | | | 1926 | 1961 | N/A | - |
| South and Western Railroad | | ACL/ L&N | 1906 | 1908 | Carolina, Clinchfield and Ohio Railway | - |
| South and Western Railway | | ACL/ L&N | 1901 | 1906 | Kingsport Southern Railway, South and Western Railroad | - |
| Southern Railway | SOU | SOU | 1894 | 1990 | Norfolk Southern Railway | - |
| Southern Freight Railroad | SFR | | 1997 | 2003 | Heritage Railroad | - |
| SouthRail Corporation | SR | | 1988 | 1993 | Kansas City Southern Railway | - |
| Southwestern Railroad | | L&N | 1852 | 1877 | Nashville, Chattanooga and St. Louis Railway | - |
| Swan Creek Railway | | L&N | 1906 | 1921 | Louisville and Nashville Railroad | - |
| Tellico Railroad | | L&N | 1887 | 1887 | Nashville and Tellico Railroad | - |
| Tellico Railway | | L&N | 1898 | 1910 | Athens and Tellico Railway | - |
| Tennessee Railroad | TENN | SOU | 1918 | 1973 | Tennessee Railway | - |
| Tennessee Railway | | SOU | 1904 | 1918 | Tennessee Railroad | - |
| Tennessee and Alabama Railroad | | L&N | 1852 | 1866 | Nashville and Decatur Railroad | - |
| Tennessee, Alabama and Georgia Railroad | | SOU | 1911 | 1922 | Tennessee, Alabama and Georgia Railway | - |
| Tennessee and Carolina Southern Railway | | SOU | 1902 | 1935 | N/A | - |
| Tennessee Central Railroad | TC | TC | 1902 | 1922 | Tennessee Central Railway | - |
| Tennessee Central Railroad | | TC | 1893 | 1897 | Tennessee Central Railway | - |
| Tennessee Central Railroad | | | 1883 | 1891 | N/A | - |
| Tennessee Central Railway | TC | TC | 1922 | 1968 | Harriman and Northeastern Railroad, Illinois Central Railroad, Louisville and Nashville Railroad | - |
| Tennessee Central Railway | | TC | 1897 | 1902 | Tennessee Central Railroad | - |
| Tennessee and Cumberland River Railroad | | | 1897 | 1915 | N/A | - |
| Tennessee, Kentucky and Northern Railroad | | | 1912 | 1934 | N/A | - |
| Tennessee Midland Railway | | L&N | 1886 | 1895 | Louisville and Nashville Railroad | - |
| Tennessee and North Carolina Railroad | | | 1900 | 1920 | Tennessee and North Carolina Railway | - |
| Tennessee and North Carolina Railway | | | 1920 | 1951 | N/A | - |
| Tennessee Northern Railway | | SOU | 1896 | 1903 | Knoxville and Ohio Railroad | - |
| Tennessee and Ohio Railroad | | SOU | 1884 | 1889 | East Tennessee, Virginia and Georgia Railway | - |
| Tennessee and Pacific Railroad | | L&N | 1866 | 1877 | Nashville, Chattanooga and St. Louis Railway | - |
| Tennessee and Sequatchie Valley Railroad | | | 1880 | 1883 | Tennessee Central Railroad | - |
| Tennessee Southern Railroad | | IC | 1881 | 1884 | Louisville, New Orleans and Texas Railway | - |
| Tennessee State Line Railroad | | SOU | 1882 | 1886 | East Tennessee, Virginia and Georgia Railroad | - |
| Tennessee Valley Railroad | | SOU | 1887 | 1888 | East Tennessee, Virginia and Georgia Railway | - |
| Tennessee Western Railroad | | L&N | 1912 | 1939 | N/A | - |
| TennRail Corporation | | | 1991 | 1993 | Kansas City Southern Railway | - |
| Troy and Tiptonville Railroad | | IC | 1887 | 1903 | Chicago, St. Louis and New Orleans Railroad | - |
| Unicoi Railway | | | 1909 | 1918 | N/A | - |
| Union Railway | URY | MP | 1886 | 1966 | Missouri Pacific Railroad | - |
| Union Railway | | SOU | 1883 | 1888 | Chattanooga Union Railway | - |
| Virginia and Southwestern Railway | | SOU | 1899 | | | Still exists as a nonoperating subsidiary of the Norfolk Southern Railway |
| Walden's Ridge Railroad | | SOU | 1877 | 1888 | East Tennessee, Virginia and Georgia Railway | - |
| Wauhatchie Extension Railway | | SOU | 1914 | 1917 | Alabama Great Southern Railroad | - |
| West Nashville Railway | | L&N | 1887 | 1887 | Nashville, Chattanooga and St. Louis Railway | - |
| Western and Atlantic Railroad | | L&N | 1848 | | | Still exists as a lessor of CSX Transportation |
| Wills Valley Railroad | | SOU | 1854 | 1868 | Alabama and Chattanooga Railroad | - |
| Yazoo and Mississippi Valley Railroad | | IC | 1892 | 1946 | Illinois Central Railroad | - |