Thousands to share in $560m toll relief scheme

But cars registered with businesses, rideshares, taxis and heavy vehicles will be ineligible for the $60 toll cap, which starts on January 1.

Eligibility for the scheme was unveiled on Friday, as the government tried to ensure commuters were the primary beneficiaries.

The cap will be restricted to state residents who hold a personal account with a NSW toll service provider and spend more than $60 a week on private trips on one tag or licence plate.

Families sharing a single toll account cannot combine their spend across vehicles, while trips on the M5 for those registered for the motorway's cashback scheme, will not count towards the cap.

Drivers spending an average of $200 per week can expect to receive approximately $7280 in rebates each year, paid quarterly.

An estimated 34,000 people in Kellyville, Baulkham Hills and Greystanes, in Sydney's west and northwest, are expected to claim some form of relief, the state government estimates.

A fair-use policy will prevent any weekly rebate exceeding $340, imposing extra costs on drivers who rack up more than $400 in tolls.

The scheme was a key election pledge aimed at winning Labor seats in western Sydney, where the bulk of the city's tollways are based.

The cap would ease living costs for families doing it tough, particularly in outer suburban areas with poor public transport, Roads Minister John Graham said.

"The toll cap criteria has been designed very carefully to prevent anyone trying to game it," he said.

"We are working with rideshare companies to ensure work trips are not claimed. This will include random audits."

Mr Graham defended the blowout in the cost of the program, budgeted pre-election at $145 million, saying Labor in opposition was unaware precisely how many people would be eligible.

"More than 700,000 people are eligible for this scheme - that is absolutely good news," he told reporters.

NRMA spokesperson Peter Khoury said if toll roads were deemed too expensive, people would not use them and the network would go broke, but the announcement was fair.

"I think it still strikes the right balance and I'm pretty sure that the public will support any measure right now that can reduce their cost of living a bit," Mr Khoury told AAP.

"Most Sydneysiders aren't going to exceed that $400 per week cap."

NSW opposition leader Mark Speakman said the announced caps were secrets withheld by Premier Chris Minns.

"He didn't tell us before the election there'd be a $400 cap," Mr Speakman said.

Interstate toll accounts, interstate toll trips and account-less toll trips will not be eligible for the cap.

A truck rebate for the M5 East and M8 will apply to all toll accounts, regardless of state.

The $60 toll cap is due to run for two years, giving the government time to overhaul how motorists pay for Sydney's sprawling network of tollways.

Drivers are slugged more than $2 billion a year in tolls, leading the Labor government to dub Sydney "the most-tolled city in the world".

Some contracts with private tollway operators will not expire until 2060.

While they cannot be torn up, a toll review led by former competition regulator Alan Fels is examining more consistent and fairer charges.

But a city centre congestion tax and a broad per-kilometre charge have both been ruled out.

Australian Associated Press