First Capital Connect (FCC) was a British train operating company, owned by FirstGroup, that operated the Thameslink and Great Northern sectors from April 2006 to September 2014 which later became the Thameslink, Southern and Great Northern (TSGN) franchise.

First Capital Connect was a major provider of commuter and regional services in London and the south east of England. It operated passenger rail services from Luton and Bedford via the Thameslink to Sutton, Wimbledon and Brighton via Central London.

It also operated commuter, suburban and regional services out of London King's Cross and London Moorgate to Hertfordshire, Cambridgeshire and Norfolk. Major destinations served included Cambridge, King's Lynn and Peterborough.

First Capital Connect ceased operations at 02:00 on 14 September 2014, when the franchise was taken over by Govia Thameslink Railway, and became part of the larger Thameslink, Southern and Great Northern franchise.

On 8 April 2005, the Strategic Rail Authority announced that Danish State Railways/EWS, FirstGroup, John Laing/MTR, National Express and Stagecoach had been shortlisted for the Thameslink Great Northern franchise. On 13 December 2005, the Department for Transport awarded the new franchise to FirstGroup, with the services operated by Thameslink and West Anglia Great Northern transferring to First Capital Connect on 1 April 2006.

The term of the franchise was originally for nine years, finishing in 2015. This was dependent on performance targets being met at the end of the fourth year, which would trigger an automatic two-year extension, and an extension for up to three years after the sixth year at the discretion of the DfT. It was announced on 5 August 2011 that the franchise would end on 14 September 2013. "This will help to facilitate the continued project delivery of the Thameslink Programme, in particular the introduction of new rolling stock, which will be completed after the expiry date of the existing franchise."

The Thameslink franchise and the Great Northern part of the West Anglia Great Northern franchise were amalgamated in preparation for the Thameslink Programme (formerly Thameslink 2000), designed to increase capacity on the Thameslink route, with trains from King's Lynn, Cambridge and Peterborough. On 24 July 2007 the government announced that it was fully committed to funding the Thameslink Programme, and the project is now largely complete.

In the early part of 2007, First Capital Connect conducted a study and undertook consultation on options for increasing the capacity of services to Peterborough and Cambridge. The final recommendations involved lengthening four peak services from eight to 12 carriages from May 2009, and adding or removing a small number of stops to balance loads between trains. 1,779 more seats have been provided during the morning peak and 2,490 during the evening peak, significantly reducing the number of rush-hour commuters unable to find a seat.^{[citation needed]}