Tasmania has almost doubled its active COVID-19 case load overnight, recording 428 new infections.
It means there are now 938 cases in the island state, up from 520 active infections on Friday.
Premier Peter Gutwein said with a highly vaccinated population Tasmania would not be heading into lockdown or closing its borders because of the climbing case numbers.
However, he did advise caution to travellers, reminding Tasmanians and visitors if they contracted the virus or became a close contact while away, they would have to isolate at their own cost.
"We're seeing a nearly 50 per cent reduction in travel into the state since case numbers started to rise on the mainland, so the border is self-regulating already to some degree," Mr Gutwein told reporters.
"Just think through your travel plans in terms of travelling interstate and, importantly, your chance of bringing home the virus to family and friends is very real."
The government is changing contact tracing and isolation rules to deal with higher case loads.
Close contacts required to quarantine will be people in a "household or household-like" situation, Mr Gutwein said.
As it moves away from PCR tests for everyone who needs screening, the state is working with Australia Post for its 170 Tasmanian post offices to become distribution points for rapid antigen tests.
"It's important that we continue to prioritise our PCR testing for those who are symptomatic, and those who have undertaken RAT tests and then have had a positive result," Mr Gutwein said.
Positive cases will now be notified by SMS before receiving more information from the public health team and filling out a survey to help to identify priority contacts.
The majority of Tasmania's active cases, 224, are being managed at home, while there are 79 people in community management clinics.
One hospital patient is being treated specifically for COVID-19 symptoms, while another person with COVID-19 is receiving treatment for an unrelated medical condition.
Five aged care facilities are working to contain virus exposures, including increased personal protective equipment.
