Small business owners subcontracted to upgrade sections of the Pacific Highway in northern NSW say they have been left "emotionally devastated" after they weren't paid for work commissioned by the Government.

Ostwald Brothers, the company contracted by the Roads and Maritime Service to upgrade the Ballina to Woolgoolga section of the highway, went into liquidation in late 2017.

NSW Labor claims 23 small businesses subcontracted by Ostwald Brothers to do carry out the work are owed $7.3 million.

Isabel Wolsey, a subcontractor whose husband operates a slim grader, said they have foreclosed the family home, relocated interstate to find work, and sold machinery and equipment while waiting for payment.

Subcontractors Isabel Wolsey, Christine Swan and Jo Franklin are calling on the State Government for help. ( ABC News: Mazoe Ford )

"We've got no super left because we're just trying to survive, we're both 70 and it's just an insurmountable situation," she said.

Christine Swan said she and her husband have had to sell one of their graders.

"It's just been devastating and the stress is unbelievable," Ms Swan said.

"We were travelling quite nicely up until we did this job, we have been on main roads jobs all around Australia but have never struck the debacle we have struck in NSW."

Jo Franklin, who operates an excavator company said subcontractors "hit a brick wall" when contacting the State Government about the payments.

"The claims are that none of the subcontractors said anything but that's absolutely ridiculous, we rely on that money coming in, to the day," Ms Franklin said.

"People were writing letters, emails, phone calls, complaining on site, turning up to the offices on site, standing down the machinery and then being reprimanded for doing that.

"And then we were basically sent out very generic fact sheets, very generic forms because the company went into administration. Nobody told us what was going on."

Minister 'well aware' of the issue

Deputy Premier and Minister for Small Business John Barilaro said he had worked in the construction industry for 20 years and was well aware of the issue and the importance of being paid.

"For those subcontractors who have now been left high and dry because of Ostwald falling apart and going into liquidation, that's tough," Mr Barilaro said.

"But also on behalf of the taxpayers of NSW, we've paid the head contractor for the work, the head contractor paid Ostwald for the work.

"Now there are issues there because Ostwald is in liquidation and the subcontractors haven't been paid."

Subcontractors claim they 'hit a brick wall' when contacting the State Government about payments. ( Supplied: Roads and Maritime Services )

Mr Barilaro said the Government had spoken to the NSW Roads Minister Melinda Pavey and the Small Business Commissioner, and were assessing all the options.

"We haven't closed the door on this, but the reality is that this is part of the commercial arrangement," he said.

"When you think about infrastructure spend and procurement of contracts … we've been maybe lucky in a way that not many other head contractors have gone belly up with people who haven't been paid."

Opposition Leader Luke Foley held a meeting with some of the subcontractors in Sydney this morning and called on the State Government to help them.

"The Government should step in here, $7.3 million is nothing to the Government of this state but it's everything to these hardworking small business people," he said.