Fulton made his international début for Australia in the 1968 Rugby League World Cup and played in the World Cup Final at the Sydney Cricket Ground. Playing as a , Fulton won his first of three World Cups when Australia defeated France 20–2. He was disappointed in 1967 missing out on the Kangaroo Squad as 2nd string to Tony Branson from the Nowra Warriors. Thereafter for the next eleven seasons he was a consistent national representative.