Labor won't reveal costings: Vic govt

Victoria's treasurer says Labor can't be trusted because it has yet to release costings for $32 billion worth of election commitments.

Treasurer Michael O'Brien said voters didn't yet know how Opposition Leader Daniel Andrews would pay for his promises, despite early voting centres opening across the state on Monday.

"Victorians are now starting to cast their votes in this critical election and they still don't know how Mr Andrews will pay for his $32 billion worth of promises," he told reporters.

Mr O'Brien said the coalition had submitted 45 policies for costing by Treasury, with 27 assessed and publicly available.

"Victorians need to know; where's the money coming from Mr Andrews," he said.

"Unless you've suddenly conjured up a magic money tree, Victorians know you can't afford your promises and that's why Daniel Andrews simply can't be trusted to lead this state."

Deputy Opposition Leader James Merlino said Labor would release full costings before the election on November 29.

"We will be making announcements through the course of this week and through the course of next week," he said.

"What we have committed all along is releasing our full costings prior to the election and that's what we'll be doing."

Accounting firm Moore Stephens is auditing Labor's books and Mr Andrews on Friday said they would sign off on each and every promise.