Relief for motorists in the "most tolled city in the world" remains some way off with formal talks to overhaul the system yet to begin.
An in-principle agreement issued on Friday and set to be signed by the end of the year signals the first stage of negotiations with Sydney's sole private motorway operator Transurban for a network-wide pricing system.
The initial agreement would clear the way for more formal discussions as the parties work to hash out a deal that would supersede existing toll arrangements.
But Roads Minister John Graham said it was too early to say when residents might start seeing relief.
"We're not saying this will be quick, we're not saying it will be immediate ... we are saying this is a serious discussion," he told reporters.
"These are complex negotiations (and) there's no way to sort through these in a quick manner."
NSW officials have been locked in talks with Transurban, which operates all 10 privately-owned toll roads in Sydney, for a network-wide system of pricing to replace the existing piecemeal scheme.
The city's remaining three toll roads are government-owned.
Premier Chris Minns - who has repeatedly referred to the NSW capital as the "most tolled city in the world" - said previously he wouldn't rule out extending end dates for toll charges on some roads as part of the planned overhaul.
The longest existing contract for Sydney's network of 13 toll roads extends to 2060.
Mr Graham said the government was negotiating for lower tolls for drivers travelling long distances under a more efficient model, but he would not confirm what solutions were on the table.
However, it passed laws in November to set up a state-owned tolling entity, to be called NSW Motorways, that will collect tolls under a revised system.
An independent tribunal will monitor prices and make recommendations, and a tolling ombudsman will deal with complaints and disputes.
In a brief statement, Transurban said it expected to continue "constructive dialogue" with the government to finalise the initial agreement before the end of the year.
Taxpayers have been subsidising drivers on toll roads under a $60 weekly cap on charges for individual users, but Mr Graham acknowledged that system could not continue indefinitely.
"If you think it's bad now, think what it will be like in 2040, 2050, or 2060 ... that's why we need to have this once-in-a-generation look at whether we can get a better result here for the city," he said.
