Thomas Michael Flanagan (born 21 October 1991) is a professional footballer who plays as a defender for EFL League Two club Colchester United.

[6] In August 2010, Flanagan signed his first professional contract with Milton Keynes Dons, on a 12-month deal with the option of a second year.

[9] A number of top performances earned him a recall[10] and was put straight into the line up for a midweek defeat at home, to Leyton Orient[11] where he made his league debut of the season in a 3–2 loss on 15 February 2011.

[21] On 26 March 2014, Flanagan joined fellow League One side Stevenage on loan until the end of the 2013–14 season.

[22] On 25 April 2014, Flanagan was recalled from his loan due to injuries and fitness concerns in the Milton Keynes Dons squad.

On 25 August 2015, Flanagan joined League One side Burton Albion on a one-year deal following his release from MK Dons.

[31] On 24 August 2016 Flanagan received his first call up to the senior Northern Ireland squad by manager Michael O'Neill.