Bannister was born in Townsville, Queensland on 3 October 1984. He won the youth javelin title at the Australian Athletics Championships in 2001. He later won five senior javelin national titles: in 2006, 2007, 2009, 2010, and 2012. He competed twice at the World Championships in Athletics, placing eleventh in qualifying in 2007 and finishing seventh in the final in 2011. He represented his country at the Olympic Games in 2008 and 2012, finishing sixth at the former and placing twenty-seventh in the qualifying stage of the latter. He won gold at the 2010 Commonwealth Games – the first and only international senior medal of his career. This made him the first Australian winner in that event for nearly fifty years, following in the footsteps of 1962 champion Alf Mitchell.