Transport consultants have received $200 million in the past three years for work done on roads of national significance.
Some $216 million has been spent since 2009 on investigation and design work for five of the seven roads - Puhoi to Wellsford, Auckland's western ring route, the Waikato expressway, Wellington's northern corridor and Christchurch motorways.
Information obtained by Radio New Zealand under the Official Information Act shows $200 million of this was paid to consultants.
Almost half, $92 million, was paid for work done on the northern corridor.
The Transport Agency says it is standard practice to use experienced and professional consulting firms to do planning, investigation and design work for large roading projects.
It says that ensures it is able to deliver the best value for money on such projects through to construction.
The agency says given that it is not unusual to spend 10% - 15% of a project's cost on investigation and design work, the $200 million spent is reasonable for a portfolio of this magnitude.
But Labour and the Greens says it's an eyewatering amount of money that could have been spent on other transport infrastructure and services.
Transport Minister Gerry Brownlee says a lot has to be done before the actual road building starts and this is money well spent.
He told Morning Report this spending is an important part of road safety.
The seven roads of national significance will cost more than $10 billion over more than a decade.