South Australia and Queensland will remove their travel restrictions on Sunday and Monday respectively.
It comes after NSW reported 11 days without a locally acquired infection.
About 180 cases were tied to the Sydney cluster, which emerged just before Christmas and prompted nationwide travel bans on the city's residents.
"Credit to New South Wales. They got on top of their cases," said Queensland Premier Annastacia Palaszczuk on Thursday.
Australia has recorded more than 22,000 cases and 909 deaths since the pandemic began - far fewer than many other countries.
In recent months in particular, the nation has taken swift and aggressive actions to contain outbreaks at their source.
Earlier this month, the Queensland capital Brisbane completed a three-day lockdown over the detection of a single case.
This week, Australia also suspended a travel bubble with New Zealand after its first Covid case in months was confirmed to be a more contagious variant.