Quarantine periods for overseas arrivals will be reduced from 14 days to seven from the same date, while the cap on home gatherings will rise from 20 people to 30.
Other internal restrictions are expected to be eased before Christmas as SA eyes a return to relative normality for the festive season.
"There has to be some reward for the sacrifices that individuals and businesses have made, and today it is with great pride I announce our COVID-ready plan for South Australia," Premier Steven Marshall told reporters on Tuesday.
"I know this will be a huge relief for so many South Australians who are wanting to get back to normality as soon as possible."
Authorities are expecting 80 per cent of South Australian adults to be fully vaccinated by November 23.
Further restrictions will be eased once 90 per cent of the population aged 12 and over has been double-jabbed.
That is expected to be achieved before Christmas, allowing quarantine to be scrapped for fully vaccinated overseas arrivals.
There will be no requirement for all individual local government areas to achieve the 80 per cent rate by November 23, but Mr Marshall said authorities would redouble their vaccination efforts in areas that were lagging.
"I think there will be a big surge now in the vaccination rate," he said.
"The health experts are now telling us that vaccination is our pathway out."
Anyone who becomes infected between the 80 per cent and 90 per cent thresholds will still need to isolate, along with their close contacts.
AAP with The Project