Railway companies of South Dakota

List of railway companies in the American state of South Dakota.

Class I railways

 * Amtrak (AMTK), passenger on freight lines
 * Burlington Northern & Gulf Railroad (BNG), freight
 * North Western Pacific Railroad (NWP), freight and passenger
 * Pere Marquette Railway (PM), freight
 * Union Pacific Railroad (UP), freight

Regional railways

 * Dakota, Missouri Valley & Western Railroad (DMVW), freight
 * Red River Valley & Western Railroad (RRVW), freight

Shortline and terminal railways

 * Black Hills Central Railroad (BHCR), freight and passenger
 * Dakota Southern Railway (DSRC), freight
 * D&I Railroad (DAIR), freight
 * Ellis & Eastern Company (EE), freight
 * Ringneck & Western Railroad (RWRR), freight
 * Sisseton Milbank Railroad (SMRR), freight
 * Sunflour Railroad (SNR), freight

Defunct railways
Years shown here refer to the period in which a given company operated in South Dakota; they may have existed elsewhere before or after these years.