Mr Nicholson said recovering fines can include wheel clamping a vehicle, seizing property or making compulsory deductions from income or a bank account.
"In cases where people clearly can't pay a fine and enforcement action is not viable, they may be brought back in front of a judge to have their fines replaced by an alternative sentence."
He said it wasn't known how many parking fines have been written off by the court.
"The court might replace fines with an alternative sentence such as community work. On these occasions the council doesn't recover any debt." Whanganui's court has one of nine associated collection units around the country chasing unpaid parking tickets.
But Whanganui's total of unpaid fines is overshadowed by more popular tourist centres such as Queenstown where that council has more than $1 million owed to it.
Regulatory staff there said while those living in New Zealand can be chased up through the courts it was almost impossible to get payment from overseas visitors.