New Brunswick Southern Railway

The New Brunswick Southern Railway Company Limited (reporting markNBSR) is a 131.7 mi (212.0 km) Canadian short line railway owned by the New Brunswick Railway Company Limited, a holding company that is part of "Irving Transportation Services", a division within the industrial conglomerate J. D. Irving.

Irving controls NBSR, its sister company Eastern Maine Railway ((reporting markEMRY)) and Maine Northern Railway ((reporting markMNRY), 258-mile (415 km) connecting Millinocket, Maine with Van Buren, Maine), under its umbrella holding corporation NBM Railways.

NBSR and EMRY form a continuous 189.5 mi (305.0 km) main line connecting Saint John, New Brunswick, with Brownville Junction, Maine. NBSR also operates an additional 41.7 mi (67.1 km) of branch lines in New Brunswick.