Casual workers, rideshare drivers and employees being hassled after hours are the biggest winners under wide-ranging changes to industrial relations laws.
Business groups have fought hard against the reforms and argue they will add unnecessary cost and complexity to their operations.
The laws cleared the Senate on Thursday by 32 votes to 29 after Labor clinched enough support from the Greens and independents.
Workers will soon have the right to ignore work calls and emails after hours.
There will be provisions for bosses calling employees about changes to their rostered shifts.
The changes will not cover managers who need to talk to businesses in other time zones overnight, as well as industries where on-call work is crucial.
The right to disconnect was championed by Greens senator Barbara Pocock and received the prime minister's endorsement.
"It will be reasonable to contact a worker if they're receiving the allowance to be on call," Senator Pocock told the Senate.
"What we need is a practical right to turn off your phone or computer outside your paid hours, we are not paid to do so, people need time to look after themselves."
Casual workers, truckies and rideshare drivers will also be better protected under the tranche of reforms aimed at closing loopholes used by employers to undermine pay and conditions.
Casuals working permanent hours will have the option to transition to permanent work and gig economy workers will get minimum standards, including conditions and pay rates set by the Fair Work Commission.
"It makes a palpable difference for workers who have had no minimum standards that they now will have some," Employment Minister Tony Burke told parliament.
"Gig workers in Australia will know that Australia is truly a country where you don't have to rely on tips to make ends meet."
Independent senators David Pocock and Lidia Thorpe supported the reforms after securing amendments.
The legislation will head to the government-controlled lower house to be ticked off before becoming law.
The coalition has slammed the changes, saying they'll stifle flexibility and put undue pressure on small business owners.
"None of the measures are designed to improve productivity, jobs, growth and investment which are the ingredients of a successful economy,'' shadow attorney-general Michaelia Cash said.
Independent senator Jacqui Lambie also expressed doubts about the right to disconnect, warning it was a last-minute surprise that hadn't been properly scrutinised.
The Tasmanian also questioned how the right would apply to existing contracts and enterprise agreements.
"We are going into really uncertain economic times this year and I just worry about that extra red tape for businesses," she said.
Farmers also hit out at the changes to casual employment.
"The system is clear and balanced," National Farmers Federation chief executive Tony Mahar said.
"Everyone knows what they're signing up for and whether an arrangement is casual or permanent.
"Take that clarity away and it's one more thing that will discourage a farmer from creating a new role."
