The new measures, which Labor has tacked on to federal government legislation relating to managed funds, would let small businesses start a court case by seeking an order that they won't have to pay the other side's legal fees.

"That will mean if they lose, they'll pay their own legal bills, but they won't be bankrupted by the QC bills on the other side," opposition treasury spokesman Andrew Leigh told reporters on Monday.

Many small businesses are put off launching cases against anti-competitive behaviour by their larger rivals for fear of being bankrupted by court costs, he said.

Labor expects the legislation to be voted on for the final time in parliament on Tuesday.

Treasurer Josh Frydenberg said on Monday it would pass on the voices, meaning the government won't call for members' votes to be counted for or against.

Both Labor and the Nationals are claiming victory.

"We are actually going to bring about equality of access to justice where people get a fair outcome, not because of the size of their chequebook and their capacity to have a legal department, but because they have a just case," former National leader Barnaby Joyce told reporters.

"This is something the National Party has been fighting for for so long and it is great to see that this looks like it is going to prevail."

Dr Leigh said the prime minister and Liberals had been fighting against this access to justice for years.

"They voted against it in the Senate as recently as Thursday night, they voted against our bill," he said.

"If (Prime Minister Scott Morrison) backs Labor's access to small business amendment in the House ... he'll do so not because he believes in it but because he's a desperate prime minister who is desperate to avoid Nationals crossing the floor against him."

Mr Morrison told parliament he would do "everything in his power" to support small and family businesses.

"This government has done more for small and family business is than any other government," he said in response to a Labor question.

Australian Associated Press