Australia is "on track to have one of the highest vaccination rates in the world" after fully vaccinating more than 80 per cent of its population, Prime Minister Scott Morrison says.
Mr Morrison announced the "magnificent milestone" on Saturday.
The national double-dose vaccination rate reached 80.2 per cent for people in the over-16 category on Friday, but only three places have actually surpassed 80 per cent.
The ACT (94.8 per cent), NSW (89.7 per cent), and Victoria (84 per cent) prioritised vaccinations in response to the Delta outbreak, but less-affected states are lagging behind the national rate.
WA, which has not recorded a COVID-19 case since October 16, is staging a "super vax weekend" to improve its rate, which is the lowest in the country at 66.2 per cent.
The NT (66.3 per cent), Queensland (66.9 per cent) and SA (69.9 per cent) are also below the national average, while Tasmania is closer with 77.9 per cent fully vaccinated.
From Monday, people who received their second dose more than six months ago are eligible for booster shots, which are not mandatory but provide further protection.
NSW Health began offering boosters at the start of the month but this week they will be available around Australia.
As well as relying on high vaccination rates to reopen the country, rapid antigen testing will also be a factor.
National cabinet agreed on Friday to develop a national framework for the use of rapid tests, which health authorities have been cautious of expanding given PCR swab tests are more reliable.
States and territories are also considering changes to isolation requirements for fully vaccinated people identified as close contacts with a confirmed case, including reducing quarantine requirements to seven days or ditching them altogether.
Casual contacts would only be asked to seek testing and isolate if experiencing symptoms but avoid high-risk settings until they return a negative result.
© AAP 2021