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Greater Anglia, which is operated by the Transport UK Group, provides passenger rail services in the East of England. It operates services on the Great Eastern Main Line from London Liverpool Street to destinations such as Norwich, Ipswich, and Colchester, as well as on the West Anglia Main Line from London Liverpool Street to Cambridge and Stansted Airport. Greater Anglia also operates regional services in Norfolk, Suffolk, Essex, and Cambridgeshire. The Department for Transport has awarded the operating contract for services until 2025 to Abellio East Anglia Limited.

London North Eastern Railway (LNER) is a train operating company in the United Kingdom that operates intercity services on the "East Coast Main Line" between London, Yorkshire, the North East and Scotland. It was formed in 2018 as a result of the UK government's decision to terminate the franchise of Virgin Trains East Coast. LNER is owned by the Department for Transport and managed by the operator of the East Coast Partnership, a joint venture between infrastructure company Network Rail and train operator FirstGroup. LNER operates a fleet of electric and diesel trains, including the Azuma, which is the fastest train in the UK.

Thameslink is a railway service in the United Kingdom that runs through central London, connecting Bedford in the north and Brighton in the south. It is operated by Govia Thameslink Railway and serves over 200 stations, including major transport hubs such as St Pancras International, London Bridge, and Gatwick Airport. Thameslink trains run every few minutes during peak hours and offer a range of services, from fast express trains to stopping services that serve local communities. The service has undergone significant upgrades in recent years, including the introduction of new trains and the completion of major infrastructure projects such as the Thameslink Programme.