Railway companies of Maine

List of railway companies in the American state of Maine.

Companies based in the United States

 * Amtrak (AMTK), passenger on freight lines
 * Conrail (CR), freight and passenger

Companies based outside of the United States

 * Canadian National Railway (CN), freight
 * Canadian Pacific Railway (CP), freight
 * VIA Rail (VIA), passenger on freight lines

Regional railways

 * New Brunswick Southern Railway (NBSR), freight and passenger
 * St Lawrence & Atlantic Railroad (SLR, SLQ), freight

Shortline and terminal railways

 * Sandy River & Rangeley Lakes Railroad (SRRL), freight and passenger; 2' gauge

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