Millson married singer and actress Caroline Fitzgerald in the summer of 1999. The two had two children. In October 2012, it was reported by various media outlets that they had divorced. Millson met his second wife
Sarah-Jane Potts whilst filming for the BBC. The two married on 31 December 2013. Millson has a stepson, Buster, from Potts' first's marriage to actor
Tony Denman. Millson and Potts separated in 2024 and began divorce proceedings in 2025. ==Filmography==