At the moment, the cheapest times in the year to travel to Sydney are July/2020 and August/2020. You will pay the most in April/2021.
Qantas Airways, Virgin Australia, Jetstar and Rex fly non-stop to Sydney.
Jetstar is the cheapest airline that flies to Sydney.
Singapore Airlines is the best airline to fly to Sydney. Qantas Airways is the best for direct flights. The best low-cost airline is Jetstar.