The reforms will address gender pay inequality and get agreements that lift wages for low-income workers sooner, but the inclusion of multi-employer bargaining and abolishing the Australian Building and Construction Commission has been controversial.

Business and construction lobbies are opposed to both.

In exchange for a new safeguard for people on welfare support and easing bargaining pressure on small business with fewer than 20 employees, up from Labor's 15, Senator Pocock agreed to give the government the final vote it needs. Having already secured Greens support, it will pass through the Senate.

The independent senator went into negotiations prepared the block the bill over concerns it was rushed. But on Sunday he rejected any suggestion his change of heart was securing additional funding for the ACT.

"These are the biggest industrial relations reforms in at least a decade," Senator Pocock said, with the potential to lift wages and boost protection for small businesses which employ Canberra's workers.

"I've made very clear that this is not something that I wanted to horse-trade on."

Weekend negotiations between Anthony Albanese and the ACT senator ran late into Saturday night, ending in the government agreeing to amendments to its bill that will have enough votes to pass both chambers of parliament without the support of the Liberal-National opposition.

The deal with Labor does not include any ACT-specific trade off in exchange for the independent senator's vote.

"This is this is the whole deal," the senator confirmed to reporters.

The centrepiece amendment the Prime Minister agreed to is a new annual expert review of welfare supports like JobSeeker, which Senator Pocock says will be a "game changer" for people who live under the poverty line on those payments.

The new annual JobSeeker review will be made publicly available two weeks before each federal budget, adding pressure for the government to justify its policies for the more than a million Australians who live under the poverty line, Senator Pocock said.

"This is now a substantially different bill to the one introduced in the House of Representatives a month ago. It is better for business, better for workers and makes sure the most vulnerable in our community are no longer left behind," he said.

Senator Pocock said he pushed the government as far as they would go in tough negotiations, dropping his opposition to the abolition of the ABCC.

While his small pool of staff worked overtime to get across the bill's detail in the small window the parliament had to consider amendments, Senator Pocock had nothing but praise for the public servants from the Department of Employment and Workplace Relations who provided briefings.

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The Prime Minister, when asked if the JobSeeker review request from the senator was a portend of how future contentious legislation would be passed, said he believed the government could trust its dealings with Senator Pocock.

"I think he's someone who is honest and straightforward, and will put forward his views and someone who the government can work with," Mr Albanese said

The government agreed to respond to the 2018 Murray Review in this term of government. The review examined options to enhance protections for subcontractors' incomes.

Civil construction will be added to the sectors exempt from multi-enterprise bargaining. Additionally, businesses with fewer than 50 employees will have an option to exit the bargaining, with the onus on those seeking multi-employer bargaining to prove a common interest of the workers across the employers.

Multi-employer bargaining will now be capped at nine months instead of six, to allow complex negotiations to proceed for longer before parties are forced into Fair Work Commission binding arbitration.

Employment Minister Tony Burke said the employers either opt-in or their workforce votes to opt-in, but the purpose of the reform was not to enable industry-wide bargaining. It will be up to the Fair Work Commission to decide if there is a common interest among the workers and whether it meets a public interest.

"Where you go sector-wide for sectors that are critical to the national economy, at that point, it is pretty hard to see things passing the public interest test," Mr Burke told Insiders on Sunday.

Employer advocates Master Business Australia and the Australian Chamber of Commerce and Industry both praised Senator Pocock's "good faith" consultation, but said the bill remained fundamentally flawed and "not fit for passage".

Denita Wawn of Master Builders said the exemptions would not spare the construction industry from disruptions from multi-employer bargaining elsewhere in the economy.

ACCI chief executive Andrew McKellar said they remained concerned that competitors can still be forced to bargain together, and the bill will do nothing to achieve the aim of increasing wages while adding to cost and complexity to Australian businesses.

"Ultimately, this bill represents a fundamental de-linkage of wages with productivity and will detract from the flexibility and dynamism required by modern economies," he said.

The legislation will be reviewed in two years, after Labor initially sought to have it reviewed after three.

The Greens' support is also needed for the reforms to pass the Senate, which was secured following guarantees parents would have an enforceable right to request unpaid parental leave and protecting the existing Better Off Overall Test coverage of prospective workers.

"This Greens strongly back most of what is in this bill, including abolishing the ABCC and multi-employer bargaining, but we wanted to ensure low paid workers wouldn't go backwards because of some of the changes," Greens leader Adam Bandt said.

The minister confirmed the government would accept the amendments of the Senate and federal MPs would briefly return on Saturday to pass the amendments in a final vote in the House.

Only five days remain for the reforms to pass the Senate before the parliament shuts for the year.

Labor needed to persuade at least one additional crossbench senator such as David Pocock or Jacqui Lambie to get the legislation through the Senate, both of whom were holding out their support in exchange for amendments.