The cost of a trip on the Northern Gateway toll road rises by 20c for cars and motorcyclists on March 1 as the Transport Agency tries to catch up with higher running costs since the route opened three years ago.
Announcing the rise for all light vehicles to $2.20 and by 40c to $4.40 for heavy commercials, the agency said by law it was allowed an annual increase to pass on costs in line with the consumers price index (CPI).
However, tolls had not been adjusted since the road opened despite inflation and the GST increase.
Agency regional director Stephen Town said inflation and GST had hit the agency's ability to keep up repayment levels on the $158 million borrowed to build the $372.5 million route. By late last year, the agency had repaid $17.5 million of the debt.
Mr Town said $29.8 million was actually taken in toll payments but the agency had paid $14.7 million in operating expenses.
"Not all these expenses are covered by toll payments with 65c from each toll going towards operating expenses.
Also, in the first 18 months of the toll road, about $3 million came from funds left over to establish the toll road.
A further $2.4 million came from administration charges collected from toll payment notices.
"The tolling business must run its operating expenses within the operating revenue that it collects from each paid toll and administration charges.
"The agency is managing its costs very tightly."
Mr Town said that if the toll had been adjusted yearly for inflation, the toll would still have to be $2.20 for light vehicles and $4.40 for heavy from March 1.
Transaction charges were introduced in August 2011 to some toll payments and would not increase.
These were 40c for payment at the kiosks at the Silverdale and Puhoi ends of the 7km route and $3.70 when payment was made by phone.
Transaction charges applied each time one or more tolls were paid for.
For example, from March 1 the total cost of buying one trip at a kiosk would be $2.60, made up of a $2.20 toll plus a 40c administration charge.
The total costs of buying 10 trips at a kiosk would be $22.40 - which is $22 for the 10 trips plus a 40c administration charge.
No administration fee was charged for tolls paid on line at www.tollroad.govt.nz or for the "set and forget" toll accounts.