Railway companies of Connecticut

List of railway companies in the American state of Connecticut.

Companies based in the United States

 * Conrail (CR), freight and passenger

Companies based outside of the United States

 * Canadian National Railway (CN), freight

Regional railways

 * Providence & Worcester Railroad (PW), freight and passenger

Shortline and terminal railways

 * Branford Steam Railroad (BSRR), freight
 * Central New England Railroad (CNZR), freight
 * Connecticut Southern Railroad (CSO), freight
 * CT Rail (CTRL), passenger on freight lines
 * Housatonic Railroad (HSRR), freight and passenger
 * Naugatuck Railroad (NAUG), freight and passenger

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