[1] A tall, powerfully built wing, Mullins played in some of the great Easts sides of the seventies, winning premierships in 1974 and 1975,[2] and finishing runners up in 1972 Grand Final.
During the 1976 NSWRFL season, Mullins played as a wing for Eastern Suburbs in their unofficial 1976 World Club Challenge match against British champions St. Helens in Sydney.
Mullins for many years owned a fish and chip shop in Sydney's Charing Cross.
[citation needed] Brothers Russell and Terry Mullins played for Sydney's Western Suburbs Magpies against Bill and his son Brett Mullins[2] is an Australian representative who has won premierships with Canberra and Sydney Roosters.
Mullins is the grandfather of the rugby league footballer for the Canterbury Bankstown Bulldogs; Jack Hetherington and Canberra Raiders outside back James Schiller.