Premier Peter Gutwein is warning people not to flout social distancing regulations by holding backyard parties as the state's pubs, clubs and casinos prepare to close at noon on Monday.
Places of worship, gym and indoor sporting centres will also close, while restaurants will be limited to takeaway only.
Nursing home visitors will be limited to two at a time for up to two hours, with children under 16 banned, unless it's an end-of-life situation.
The typically combative Premier blasted the disastrous example set by those in Great Britain.
"We are not going to go through the farcical situation that we saw in Britain, where "last drinks" brought hundreds of people together for one last night, which must have - there is no doubt in my mind - further spread the virus in that country," said Mr Gutwein.
The Premier says schools and childcare centres will remain open for the time being.
"Tomorrow night at National Cabinet we will be looking again at the issue of private gatherings," he said.
"This cannot be a migration from the pub to the backyard; this is important, this will save lives."