Trains to Portsmouth

East Midlands Railway is a train operating company that provides passenger services across the East Midlands region of England. It was formed in 2019, taking over the franchise previously operated by East Midlands Trains. The company operates services on routes including London St Pancras to Sheffield, Nottingham to Liverpool, and Norwich to Liverpool. East Midlands Railway also operates local services within the East Midlands, connecting towns and cities such as Derby, Leicester, and Lincoln.

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.

London Overground is a suburban rail network in London, England. It was created in 2007 by the merger of the former Silverlink Metro service with other rail services. The network consists of 112 stations and serves 23 London boroughs. London Overground operates on these routes, which include Highbury & Islington to West Croydon/Clapham Junction/Crystal Palace, Richmond/Clapham Junction to Stratford, Gospel Oak to Barking Riverside, Watford Junction to Euston, Liverpool Street to Enfield Town/Cheshunt, Liverpool Street to Chingford, and Romford to Upminster. Overground is operated by Arriva Rail London under a concession from Transport for London.

South Western Railway (SWR) is a train operating company in the United Kingdom that operates passenger services in South West England and parts of Southern England. It was formed in 2017 as a result of the merger of South West Trains and the Island Line Trains. SWR operates services to major cities such as London, Bristol, Southampton, and Portsmouth, as well as smaller towns and villages in the region. The company operates a fleet of modern trains, including electric and diesel multiple units, and provides a range of ticketing options, including season tickets, advance purchase tickets, and flexible fares. SWR is owned by FirstGroup and MTR Corporation.

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.