Deloitte's head of infrastructure Paul Callow says a congestion charge in Auckland would provide a stable and predictable source of income to fund the city's transport projects.
Mr Callow conducted a study for the Ministry of Transport several years ago evaluating five different congestion charges, two of which have been picked up by an Auckland council think-tank.
On Monday, Transport Minister Gerry Brownlee told Radio New Zealand that a congestion charge would not provide a reliable source of revenue to fund Auckland's future infrastructure developments.
But Mr Callow says that in London income from a congestion charge has been stable.
"The experience in London is that the effect is almost instantaneous in that the day you introduce the charge you get a significant drop in traffic and congestion but then it tends to creep back a little bit and remain stable thereafter."
In London, he says, there was an initial 20% drop which has levelled out to a stable to 15% reduction in traffic.
He says the initial charge prices a lot of people off the road and that encourages them to use public transport.