Born in Oxford, Thomasin trained at Swindon Dance and Rambert School before joining Rambert (2003-2011). He toured nationally and internationally with the company, creating roles and performing works by many acclaimed choreographers such as Javier de Frutos, Wayne McGregor, Siobhan Davies, Fin Walker and Doug Varone. In 2009, he received a Critics’ Circle National Dance Award for his performance in Christopher Bruce’s Hush.

As a freelance dance artist, Thomasin toured extensively with Russell Maliphant (2012-2016) and Company Chameleon (2012-2020) alongside projects in dance, opera, theatre and film including: Boris Charmatz (Terrain), Merce Cunningham Trust, The Royal Ballet, Royal Opera House, Candoco Dance Company, Akram Khan (London 2012 Olympic Games Opening Ceremony), Alice Oswald, National Theatre, Young Vic, Joe Wright, Sidi Larbi Cherkaoui and Mad Dogs Dance Theatre.

Since 2017, Thomasin has pursued an interest in health and healing through movement, stillness and writing in nature. This creative practice led him to studying Chinese Medicine and in 2022, he became a licensed practitioner of Classical Five-Element Acupuncture.