Unlike previous lockdown rules, work or exercise is not a reason to leave home for the unvaccinated.
"Today's escalation in case numbers is concerning," Chief Minister Michael Gunner said.
"Our community transmission rate has grown in recent days."
There are two people in intensive care in the NT and one person on a ventilator.
In Victoria, it's been confirmed density limits of one person per two square metres will be reintroduced at hospitality venues including pubs, restaurants and cafes from Friday. Cinemas and theatres, where people are seated and masked, will be exempt.
Health Minister Martin Foley will also sign off on a new category of COVID-19 contact later on Thursday: anyone who returns a positive rapid antigen test (RAT) will be classified as a "probable case".
He said the category, made official from midnight, would impose the same obligations and rights on people who have a positive PCR test, including access to clinical support and state and federal financial support.
631 people are in hospital in Victoria, an increase on the previous day's figure of 591. The state has 100 people in ICU.
The state posted 21,997 cases and six deaths on Thursday, a surge on Wednesday's 17,636 infections.
In NSW, as of 8pm on Wednesday, there were 1,609 people in hospital in NSW, up from the 1,491 reported 24 hours earlier.
There are 131 patients in intensive care.
NSW has also recorded 34,994 infections of COVID-19 and six deaths - a slight decrease on Wednesday's 35,054 cases.
One of the new deaths was a vaccinated ACT man in his 20s who died at Sydney's St Vincent's Hospital. The other fatalities were four men and a woman aged between 60 and 90. Two were from Lake Macquarie in the Hunter Region and three from western Sydney.
In both Victoria and NSW, approximately one in three people tested returned a positive result in the most recent reporting periods.
Many PCR testing sites across Australia and pathology labs remain strained.
That comes despite changes introduced by National Cabinet on Wednesday, meaning people who record a positive from a RAT will no longer have to get their results confirmed by a PCR. That decision is expected to ease some of the pressure on PCR sites, though RATs remain in short supply.
What's happening in the other states?
There are now 284 people in hospital in Queensland, a jump from 265 patients on Wednesday. There are 12 people in ICU.
The state also posted 10,332 new cases of COVID-19 - up from 6,781 infections - and one further death on Thursday. The man in his 80s died on 27 December, but his death has now been confirmed as COVID-related.
Queensland's Chief Health Officer John Gerrard said the number of patients in hospital with COVID-19 is "increasing steadily."
"The sheer number of patients that are going to get infected in Queensland over the next few weeks means that even a small proportion of this very, very large number will end up in hospital," he told reporters.
He said the state's case numbers are "a gross estimation of the true number" of infections."
South Australia posted 3,070 infections on Wednesday, a decline from the 3,493 cases recorded the previous day.
There are 12 people in intensive care and 123 patients in hospital, down from 125, while in Western Australia, there was one new local case recorded on Thursday.
Source: Chris Hyde/Getty Images
Tasmania, meanwhile, has reported 751 new COVID-19 cases, with one person admitted to hospital.
The caseload came from 2,958 tests and represents a drop from Wednesday's record of 867.
One patient is being treated specifically for coronavirus symptoms, while four other people in hospital have COVID-19 but were admitted for unrelated medical conditions.
State Public Health Director Mark Veitch has said one-in-50 Tasmanians could be active cases in about a week, up from the current rate of about one-in-170.
In the ACT, 992 cases of COVID-19 have been reported - the territory’s highest daily tally of the pandemic.