The most expensive month to fly to Australia is consistently December, specifically the weeks surrounding Christmas and New Year. This period represents a "perfect storm" of high demand: it is the peak of the Australian summer, the primary school holiday period for locals, and a massive time for international tourists visiting "bucket-list" destinations like Sydney for the fireworks. Fares during late December and early January can be double or triple the price of shoulder-season tickets. Another secondary peak occurs in June and July, which aligns with Northern Hemisphere summer vacations and Australian "winter escape" patterns to the northern parts of the country. If you are looking for value, February and March are considered the best months, as the holiday rush has ended but the weather remains warm and pleasant across most of the southern states.