The Greens’ proposal would cost $54 billion over the next four years and $74 billion over the decade, according to modelling carried out by the Parliamentary Budget Office.

Modelling showed university students would save $5500 a year without having to pay back HECS debt under the policy.

Greens higher education spokeswoman Mehreen Faruqi said the measure would provide greater cost-of-living relief.

"Wiping student debt will put money back in the pockets of people who desperately need it to make ends meet, pay rent or save for a deposit for their first home," she said.

"With everything from rents to grocery bills through the roof, wiping all student debt will make a real, tangible difference to so many people doing it tough."

The federal government has already outlined a plan to cut student debt by 20 per cent if it wins the next election, but Greens’ leader Adam Bandt said there was support for the policy to come into effect sooner.

The government policy would affect $16 billion of student debt, with those with an average HECS bill of $27,600 to have it reduced by $5500.

With AAP.