John "Jack" Chalmers GC (11 March 1894 – 29 March 1982) was a New Zealand-born Australian exchange recipient of the George Cross, the highest decoration for gallantry awarded to civilians or to military personnel for actions "not in the face of the enemy" in the United Kingdom and Commonwealth. A member of the North Bondi Surf Life Saving Club, Chalmers was awarded the Albert Medal in 1922 for his actions in rescuing a swimmer during a shark attack at Coogee Beach.