Sectorisation

The history of rail transport in Great Britain 1948–1994 covers the period when the British railway system was nationalised under the name of British Rail (initially known as British Railways), until its eventual privatisation in 1994.

The railway system in this period underwent modernisation, reorganisation and rebranding, some of which proved controversial. The use of steam locomotives on the network also ended in this period. Due to falling passenger numbers, rail subsidies from the government were necessary to keep the railways financially viable. Concerns about the levels of these contributed to the Beeching cuts which closed down many less well used lines.

The Transport Act 1947 nationalised nearly all forms of mass transport in Great Britain and came into effect on 1 January 1948.British Railways came into existence as the business name of the Railway Executive of the British Transport Commission (BTC) on 1 January 1948 when it took over the assets of the "Big Four" railway companies.

A small number of independent light railways and industrial railways, which did not contribute significant mileage to the system, were not included in British Railways; nor the Glasgow Underground and London Underground, already both public concerns, the Liverpool Overhead Railway, and non-railway-owned tramways. The Northern Counties Committee lines owned by the LMS were sold to the Northern Ireland government, becoming part of the Ulster Transport Authority (UTA) in 1949.

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