List of constituents of British Railways

The following is a list of constituents of British Railways. British Railways (BR) was formed by nationalisation on 1 January 1948 in accordance with the Transport Act 1947. It had four major constituents, but there were a number of joint lines between these, and additionally some light railways were taken into the fold. Even then, some light railways were not nationalised.

The major constituents (the "Big Four") were:

Joint railways between the four major constituents (and others) were:

Joint railways between the four major constituents and others were:

Irish railways owned by the LMS (the Northern Counties Committee lines) were also acquired but were quickly sold on to the Government of Northern Ireland.

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