In 2003, Jones set an Australian record in the 200-metre individual medley earlier in the year, in an experimental event. Later at the 2003 World Aquatics Championships in Barcelona, Spain, she started setting a world record in the semifinals of the 100-metre breaststroke (1:06.37). However, she succumbed to nerves in the final and came third, with Luo again winning the event. She also achieved a silver in the 200-metre breaststroke in Barcelona, behind Amanda Beard in (2:24.33). She collected a bronze in the medley relay.