Born into a musical family, Thomas' early studies were with John Senter. He went on to study at the Royal Birmingham Conservatoire with John Todd, Philip Higham and Alexander Baillie, graduating in 2014 with distinction.
Thomas' solo career began as a postgraduate student. Having already performed at the Conservatoire concert series' on numerous occasions, he has also performed across the country with his father, Richard McMahon as pianist. He has appeared as soloist with orchestras based in Birmingham, Redditch, South Wales, Swindon and Wolverhampton and Yorkshire.
A keen chamber musician, Thomas has performed at venues such as the Wigmore Hall in London, and in 2015, at the BBC Proms in London, making his Proms and BBC Radio 3 debut. He has extensively explored the Piano Trio repertoire, having performed both trios by Schubert, as well as trios by Beethoven, Brahms, Dvorak, Haydn, Shostakovich, Smetana and Ravel. In April, he performed live on BBC Radio 3 with his string quartet as part of the 'Sounds of Shakespeare' festival. He has recently performed alongside pianist Iain Burnside, baritone Roderick Williams and chamber musicians Simon Smith, Robin Ireland, Krysia Osostowicz and Susanne Stanzeleit.
Thomas also regularly appears with the Cardiff Sinfonietta and as a pedagogue, he teaches the Cello at Wolverhampton Grammar School and the Priory School in Birmingham.
Thomas plays on a modern cello by John Dilworth. Built in 2004, it is modelled on Montagnana's famous "Sleeping Beauty" made in 1739.