Thomas rose to prominence in British gymnastics, when he won the British all-around title in 2008. Floor is his best event, and during his Senior career he has won several silver medals on floor in International competitions. At the 2009 World Artistic Gymnastics Championships in London, he placed 6th in the All-Around. He was also part of the British men's team that represented Great Britain at the 2010 World Artistic Gymnastics Championships in Rotterdam and the 2011 World Artistic Gymnastics Championships in Tokyo.