What will change under Labor's new industrial relations laws?

The Albanese government has passed the biggest overhaul to workplace laws in more than a decade, rejecting opposition claims the changes will force businesses to close and unions to strike more.

But will it do anything to help workers and kickstart the economy?

The most talked about changes have been around multi-enterprise bargaining, which make it easier for single-interest and supported bargaining, allowing employees in similar industries or the same location and low-paid industries to bargain together.

But Andrew Stewart, Professor of Law at the University of Adelaide, believes the changes that will impact most people are other ones.

"I'm actually sceptical about how easy it will be for those provisions to be used. There are an awful lot of hurdles that have to be overcome for employers to be compelled to engage in that type of bargaining," he said.

Instead, he thinks changes in the legislation that address pay equity, restrict fixed-term contracts and make it easier for employees to request flexible work agreements will have a broader impact on more Australians.

"For businesses that are already involved in negotiating enterprise agreements, the changes will make a little bit of difference in terms of making it slightly quicker and easier to get agreements approved," Professor Stewart said.

The Labor government also plans more workplace changes next year, designed to "close the loopholes that are undermining job security and wage growth".

Labor claimed the previous Liberal government had kept wages deliberately low, and one of Labor's key election promises was increasing pay and making jobs more secure.

Professor Stewart said it is "certainly true that the government kept wages deliberately low in the sectors over which it has direct control and also failed to take steps to encourage wage increases in the parts of the private sector over which it has no control".

Employment and Workplace Relations Minister Tony Burke said the only way to make these changes in the workplace and economy was to change the law.

Despite the bill successfully passing before the end of the year, employees are unlikely to get a wage rise by Christmas.

Professor Stewart said people are not likely to get pay increases in the short-term, but rather in the medium to long term.

"New supportive bargaining provisions are ones which have a lot of potential in industries like child care and aged care. But it's going to take a while to see whether or not anything comes out of that and in many ways, if workers in those industries are going to be getting pay rises over the next few years," he said.

"It may be more likely to come from pay equity claims, or work value claims, rather than a big new system."

ANU Associate Professor Kailing Shen said, "this law fits well with what will improve the welfare of Australian workers as well as what will lead to a more productive economy."

Opposition workplace relations spokeswoman Michaelia Cash said the changes are a "radical shake-up" and the bill's success will be judged through Australia's inflation level.

"If prices rise for Australian families this will also mean failure for this government's bill,'' Senator Cash said.

Business groups say the changes will increase strikes, force businesses to reduce staff and opening hours and potentially close altogether.

ACT senator David Pocock secured amendments to the bill that he says will safeguard small businesses, excluding businesses with fewer than 20 employees from the single-interest multi-enterprise bargaining stream, an increase from Labor's proposed 15.

Professor Stewart said claims the bill would increase strikes were nonsensical because unions no longer have the power they had in the 1970s.

"There is no way we are going to see a new wave of industrial action because of these changes, there aren't enough union members," he said.

"Most union members today do not take industrial action. We're a nation that lost the sense of collective voice and collective action. A lot of people just don't feel they can afford to take industrial action."

Associate Professor Kailing Shen said businesses will need to work with interest groups for improved productivity and a lot of work is still needed in the future to improve the economy.