The publicly-owned body will be the long-term replacement for the previous privatised rail franchising system which lasted from 1996 until its effective abolition in 2021.

All train operating companies will be taken into public ownership as their contracts expire and then folded into GBR, reunifying passenger services under one publicly-owned entity for the first time since the privatisation of British Rail.

In September 2024, the DfT set up Shadow Great British Railways to start the work of GBR prior to its legal establishment by Parliament.

During 2020, in the midst of the COVID-19 pandemic, all passenger train operating companies (TOCs) entered into Emergency Recovery Measures Agreements with the UK and Scottish Governments.

[8] Andrew Haines and Peter Hendy, who were the CEO and chairman of Network Rail respectively, were appointed to oversee the establishment of GBR.

[13] The 2023 King's speech announced the progression of a draft Rail Reform Bill which would enable the establishment of GBR, although it has not been timetabled in the Parliamentary programme.

[15] Prior to the 2024 general election, the Labour Party confirmed that it would be seeking to bring railways into public ownership,[16] while preserving the role of open-access operators.

"[23] On 3 October, Laura Shoaf, previously chief executive of the West Midlands Combined Authority, was appointed as chair of Shadow GBR.

[24] In December 2024 it was announced that the first three train operating companies to be brought into public ownership as part of the government’s plan would be South Western Railway (May 2025), c2c (July 2025) and Greater Anglia (Autumn 2025).

[28] A shortlist comprising Birmingham, Crewe, Derby, Doncaster, Newcastle upon Tyne, and York was announced in July 2022,[29] using the following criteria: alignment with "levelling up" objectives; connected and easy to get to; opportunities for GBR; railway heritage and links to the network; value for money; and public support.

[30][31] Great British Railways is planned to operate in the existing areas of Network Rail, i.e. England, Scotland and Wales.