The minor party hopes the policy will benefit school students, carers, low-income families and the unemployed.

Greens leader Adam Bandt said the COVID-19 pandemic showed how important internet access was.

"During the last two years of lockdowns, some families had to park outside the local library to access free internet so their kids could do their school work," Mr Bandt said.

"At a time when more people are having to rely on the internet to work, study, socialise, shop, and pay their bills, Australia's digital divide is increasing."

The free high-speed net would be free to anyone with a government healthcare card with about 1.5 million Australians expected to benefit.

Costing by the Parliamentary Budget Office has priced the policy at $800 million per year.

Labor promised last year to spend $2.4 billion on improving full-fibre NBN access for homes and businesses, with the full-fibre technology providing faster speeds.

The NBN has been wracked by concerns over whether it's actually delivering on high speeds, with the competition watchdog last year saying customers were getting lower-than-expected speeds due to the current copper network implemented by the coalition government.

Australian Associated Press