Thomas made his senior debut for Swansea on 19 September 2012, coming on as a replacement in a 14–25 home loss to Cross Keys.
[3] Thomas impressed many with his performances for Swansea during the 2012–13 season and earned a call-up to the Ospreys regional team, making his professional debut on 9 November 2012 in a 33–27 win against Gloucester in the LV= Cup.
[2] On 3 July 2019, Thomas signs a one-year deal with Bristol Bears in the Premiership Rugby for the 2019–20 season.
[6] On 9 March 2020, Thomas would rejoin his home region Ospreys on a two-year deal in the Pro14 from the 2020–21 season.
[9] He went on to make 20 appearances for the U20's, including starting the 2013 IRB Junior World Championship final loss against England U20.