By Luke Costin in Sydney

THE lid has been lifted on Sydney’s toll road burden, which is expected to cost drivers a minimum of $123 billion over nearly four decades.

Modelling by NSW Treasury and transport officials estimates $64 billion alone will paid under a deal struck by the previous coalition government with Transurban for the 33-kilometre WestConnex system.

“You can’t even get a mobile phone contract without being told the minimum payment,” Roads Minister John Graham said in a statement on Monday.

“And yet, NSW motorists have been signed up to more than $100 billion in toll costs without any disclosure under the former Coalition government.”

The toll bill, projected out to 2060, takes in figures for privatised concessions, including the entire WestConnex system, NorthConnex, the Eastern Distributor, M2 and M7.

It also includes figures for the government-owned Sydney Harbour Bridge and tunnel, and future M6 stage one.

The total is the overall bill that will potentially be paid by motorists and from which operators pay for their running costs, maintenance and other charges.

It comes as drivers wait to discover if NSW Labor’s marquee election commitment to cap road tolls will apply to them.

About one in 10 drivers are expected to start sharing more than $560 million in toll refunds over two years when a $60 weekly toll cap takes effect in January.

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.

But Mr Graham last week declined to say how exactly the cap would be applied, including in the case of two family members sharing two tags on one toll account.