The Thameslink Southern and Great Northern (TSGN) franchise was formed in 2014 in preparation for the completion of the Thameslink Program. The franchise initially consisted of only former Thameslink Great Northern routes. On the 25th July 2015, the South Central and Gatwick Express franchises merged into TSGN, both retain their existing identities.
Go-via won the franchise and began operating in September 2014 as GTR (Go-via Thameslink Railway).
The existing Southern identity used during the South Central franchise was retained.
| Current franchises|
Chiltern | East Anglia (Stansted Express) | East Midlands | Essex Thameside | Greater Western | InterCity East Coast | InterCity West Coast | Merseyrail | New Cross Country | Northern | ScotRail | South Eastern | South Western (Island Line) | Thameslink, Southern and Great Northern (Gatwick Express) | TransPennine | Wales and Borders | West Midlands