 Mossop became a life member of the New South Wales Rugby League (NSWRL) in 1999 in recognition of services to the game.In 2006, Mossop was named in both the Manly Rugby League and Manly Rugby Union "best ever" sides, highlighting his enormous contribution to both codes.Rex Mossop was awarded the Australian Sports Medal on 24 October 2000 for services to Rugby League.