People can now "refuse to monitor, read, or respond to" their employers' attempts to contact them outside work hours -- unless that refusal is deemed "unreasonable".

The law is similar to those of some European and Latin American countries.

Unions welcomed the legislation, saying it gave workers a way to reclaim a work-life balance.

"Today is a historic day for working people," said Michele O'Neil, president of the Australian Council of Trade Unions. 

"The union movement has won the legal right for Australians to spend quality time with their loved ones without the stress of being forced to constantly answer unreasonable work calls and emails," she said.

"Australian unions have reclaimed the right to knock off after work."

Prime Minister Anthony Albanese hailed the reform pushed through by his centre-left Labor government.

"We want to make sure that just as people don't get paid 24 hours a day, they don't have to work for 24 hours a day," he told national broadcaster ABC.

"It's a mental health issue, frankly, as well, for people to be able to disconnect from their work and connect with their family and their life."

But the reforms got a cool welcome from Australian industry leaders.

"The 'right to disconnect' laws are rushed, poorly thought out and deeply confusing," the Australian Industry Group said in a statement.

"At the very least, employers and employees will now be uncertain about whether they can take or make a call out of hours to offer an extra shift," it said.  

The law, enacted in February, came into force for medium-sized and large companies as of Monday.

Smaller companies with fewer than 15 employees will be covered from August 26, 2025.

"We encourage workplace participants to educate themselves on the right to disconnect and take a commonsense approach to applying it within their workplace," said the head of Australia's workplace relations regulator, Fair Work Ombudsman Anna Booth.

Under the law, workers may be ordered by a tribunal to stop unreasonably refusing out-of-hours contact, and employers likewise may be ordered to stop unreasonably requiring employees to respond, it said.

The question of what is reasonable will "depend on the circumstances", the fair work ombudsman said in a statement.

Deciding factors may include the reason for the contact, the nature of the employee's role, and their compensation for working extra hours or being available, it said. 

France introduced the right to disconnect in 2017, hoping to tackle the "always on" culture facilitated by smartphones and other digital devices.