South Australia recorded 2298 new cases of COVID-19 on Sunday, up almost 200 cases from the day before.
There are 82 people in hospital, which has doubled over the weekend with 40 people in hospital two days ago.
Seven people are in intensive care.
Premier Steven Marshall said the state has flexed up available hospital beds across the system.
"Omicron is a complete and utter game changer for us here in Australia," he said on Sunday.
"The COVID-ready expenditure we had was originally for Delta, we have significantly flexed that up and the additional capacity comes on when it is needed.
"We are very much within our current capacity."
Mr Marshall said he was concerned about the number of children catching the virus.
But the premier said he was delighted with the decreased mobility in the state on New Year's Eve.
"I want to thank every South Australian for doing the right thing to protect themselves and their families and the broader South Australian community," he said.
