After announcing the state's hard border will reopen on March 3 yesterday, Western Australia had 257 new local infections, passing yesterday's previous record for daily cases of 194.
There are still no people in hospital with the virus.
NSW has recorded 7615 new infections, down from yesterday's 9243.
A further 12 people have died in the state, but hospitalisations have fallen with 1297 receiving care. Of these, 81 are in ICU.
In Victoria, 6280 new cases were recorded, down from the 6935 yesterday.
Twenty more people have died in the state, as hospitalisations fall to 365.
Queensland has also recorded a decrease in new infections, with 4919. Ten deaths were reported, while hospitalisations rose slightly to 414, up from 408 yesterday.
The number of ICU admissions has also increased, up by two to 36.
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Restrictions ease across two states
The decline in cases come after restrictions were eased in both states.
Density limits in hospitality venues have been scrapped, people will no longer need to check-in at supermarkets and retail venues, and dance floors are officially back in both states.
NSW Premier Dominic Perrottet is reportedly further considering ridding schools of masks and rapid antigen tests.
The new rules would apply to primary and high-school students and comes several weeks after twice-weekly compulsory RATs were introduced.
A decision is expected to be made next week.