As a member of the University of Toronto Track Club, Jill represented Canada numerous times in multi-event competitions including the 1984 Olympic Games in Los Angeles (United States), however her ultimate achievement took place at the 1982 Commonwealth Games in Brisbane (Australia), where she claimed the bronze in the heptathlon at the age of 24.

Earlier that same year, Ross accepted an invitation to compete at the Gotzis Hypo multi-event competition in Austria, where she went on to set a Canadian record with 6,110 points – smashing the record held by Diane Jones-Konihowski. Her fifth-place finish overall solidified her position as one of the world’s best heptathletes, as Gotzis was acclaimed as the “unofficial” world championships. At the Gotzis one year later, Jill would again finish in with 6,042 points.

Among her many other achievements, Ross earned a bronze medal in the pentathlon during the 1979 Pan American Games in San Juan (Puerto Rico), the same year she won the national championship. In 1982, Jill also set a Canadian record for the indoor pentathlon with 4,550 points, which stood for 34 years until Brianne Theisen-Eaton surpassed it.