ACT residents will soon be able to travel to South Australia without undertaking two weeks in quarantine.
South Australian Police Commissioner Grant Stevens announced on Tuesday the state border would reopen to the ACT from midnight.
ACT residents would be required to declare they had not been outside the territory in 14-days prior to arriving in South Australia and complete a pre-approval form online.
"This is our way of assuring, as best as possible, that those people travelling between South Australia and other places have not exposed themselves unnecessarily to the risk of contracting COVID-19," Commissioner Stevens said.
Canberrans must travel directly via air or must quarantine on arrival.
"It's simply not possible for us to be confident a person driving from the ACT to South Australia has not had contact with the NSW community," he said.
For weeks, the South Australian government said the nation's capital could not be separated from surrounding NSW as that state grappled with growing community transmission.
However, Commissioner Stevens said the required declaration would lower the risk.
"I am optimistic about NSW, the advice I've been provided certainly suggests they are on the right pathway to eliminate community transmission sooner rather than later," he said.
The state border with NSW would not reopen until there had been 14 days without community transmission, Comissioner Stevens said.
ACT Chief Minister Andrew Barr said the decision was an "important breakthrough" in restarting domestic aviation as one of the first jurisdictions to treat the ACT independently of NSW.
"They have been able to decouple ACT and NSW which is something I've been asking for, for some time," he said.
"I suspect some of the other states will watch this closely and be encouraged by South Australia's move, encouraged by the ACT's pandemic management to date."
ACT Senator Zed Seselja welcomed the announcement, saying it was a sensible decision from the South Australian government and he was pleased a further sense of normalcy would return to Canberrans' lives.
"The ACT is not part of NSW, we are a separate jurisdiction," Senator Seselja said.
"We have done the right thing as a territory and I think Canberrans should be rewarded for that.
"I would say to Queensland that Canberra is not a hotspot and we should have the same freedom to travel to Queensland that the South Australian government has now seen fit to grant to Canberra residents."
A Queensland government spokesman said the state's border restrictions were determined by health advice and would be reviewed at the end of the month.
Three Qantas Canberra to Adelaide flights depart Canberra Airport each week, on Monday, Thursday and Friday. The airline said it would look to increase services to match demand.
Canberra Airport managing director Stephen Byron has been waiting for this announcement since June.
"It's certainly good news to recognise Canberra is not a hotspot," he said.
"There's a huge pent up demand to be able to take a holiday.
"It's going to allow families to see each other ... so I think you're going to see a big pent up demand of family reunions and then of course there's business activity and there's a lot of defence business between Adelaide and Canberra."
He hoped the ruling would set a precedent for other states who had locked out Canberrans claiming the ACT, which has not had a coronavirus case for two months, was a hotspot.
"States should be able to look at the fact that Canberra is COVID free and they should be able to look at their colleagues in the Northern Territory and South Australia opening their borders to us," Mr Byron said.
"There's a great opportunity for us to prove the concept that we can have this and make it work.
"Canberra is not in the same basket as Sydney was."
Mr Barr said Tasmania was the next state likely to open up to the ACT and conceded a travel bubble with Western Australia was a way off.
A spokesman for the Western Australian government reiterated that the state would not be opening any travel bubbles with other jurisdictions.
"WA's hard border will remain in place for the time being as it allows us to better protect the health of our citizens, and allows us to open up our economy to a far greater degree," the spokesman said.
Senator Seselja added that when "unnecessary border restrictions" around Australia were lifted it would bring great benefits for both Canberrans and Australia more generally.
South Australian Health Minister Stephen Wade said the announcement was a first step towards a COVID normal.
"I have no doubt this will be very welcome news to many people in the ACT and, to be frank, many people in South Australia who want to go there," he said.
"This is only a first step, we are hopeful NSW will continue to make good progress."