Bronte and older sister Cate Campbell created history in London as the first Australian sisters to compete in the same event at the same Olympic Games. Bronte finished second in the 50m freestyle at the Olympic trials behind her older sister Cate, prompting jubilant celebrations. At the Olympic Games in London Bronte finished fourth in her semi-final to miss the final by 0.23secs.
Bronte also competed at the 2009 Australian Youth Olympic Festival where she won gold in the 50m freestyle just as her sister Cate did two years previously. Two years on at the 2011 Junior World Championships in Peru, Bronte won the 50m freestyle in a championship record time of 25.22 seconds.