Melbourne became Australia's most populous city, surpassing Sydney, which had held the title for over a century. According to official statistics, there are now almost 19,000 more citizens in Melbourne than in Sydney.
It all boils down to a boundary change, since the Melton suburbs were included into the city.
"Until the 2021 census definition, the Sydney significant area had a higher population than Melbourne. However, with the amalgamation of Melton into Melbourne in the latest… classification, Melbourne has more people than Sydney - and has had since 2018," a representative of the Australian Bureau of Statistics reportedly told a local newspaper.
The Australian Bureau of Statistics (ABS) includes any connecting suburbs with more than 10,000 people as part of a city’s “significant urban area”. It should be noted that Melbourne used to be Australia’s most populous city for a solid period, thanks to the late 19th century gold rush that sparked an influx of migrants. However, in 1905, Sydney took over the mantle of the continent's most populous city and has held this title until 2023.