Compare the road tax of a RUC vehicle against a petrol car. Electric and diesel vehicles pay road user charges of $76.00 per 1,000 km; plug-in hybrids pay $38.00 per 1,000 km. Petrol cars instead pay fuel excise duty of about 70 cents per litre at the pump, and do not pay RUC.
Enter your annual distance and the petrol car's fuel use, and this calculator shows annual RUC (including admin fees), annual petrol excise, the difference, and which is cheaper on road tax alone.
| Annual km | RUC (incl admin) | Petrol Excise | Difference | Cheaper |
|---|
Every vehicle on New Zealand roads contributes to the National Land Transport Fund, which pays for road building, maintenance, public transport and road safety. Petrol vehicles pay through fuel excise duty (FED) built into the pump price, currently about 70 cents per litre. Electric vehicles, diesel vehicles and plug-in hybrids pay little or no fuel excise, so instead they buy road user charges (RUC) in 1,000 km blocks. This calculator puts the two side by side so you can see which pays less road tax for the same distance.
Using the calculator defaults: an electric vehicle (RUC $76.00 per 1,000 km) driving the New Zealand average of 11,500 km per year, buying RUC in 5,000 km blocks online ($12.44 admin fee), compared with a petrol car using 8 L/100km and paying 70 cents per litre in excise.
On road tax alone the petrol car is cheaper by about $267 a year. But that is only one part of the picture: charging an EV at home costs roughly 3 to 5 cents per km versus 12 to 18 cents per km for petrol fuel, so the EV's lower running costs typically more than make up the road tax gap. Total cost of ownership usually still favours the EV or diesel.
Fuel excise duty is a per-litre tax included in the price of petrol. It is the petrol equivalent of RUC: a way of charging drivers for road use roughly in proportion to how far they drive (since fuel burned rises with distance). Petrol vehicles pay excise automatically every time they fill up, which is why they do not also buy RUC. Diesel is sold without this excise, so diesel vehicles pay RUC instead. The headline rate is around 70 cents per litre, though the exact figure changes with government policy.
RUC is a flat charge per kilometre, so a thirsty petrol car and an efficient one would pay the same RUC. Petrol excise, by contrast, depends on how much fuel you burn, so an economical petrol car pays less excise per kilometre than a thirsty one. For a typical efficient petrol car (around 8 L/100km) the excise works out lower than RUC for the same distance. A thirstier petrol vehicle (say 11 to 12 L/100km) can end up paying roughly the same as, or more than, RUC. Try changing the fuel use figure in the calculator to see the crossover point.
The government has announced plans to move every vehicle, including petrol cars, onto road user charges and to remove fuel excise duty, with a transition targeted around 2027. The Road User Charges Act 2012 is being amended to allow private providers to run a more technology-enabled system. The change has been announced but not finalised, and the final pricing and start date are not yet confirmed. Until then, petrol cars keep paying excise at the pump and only EV, diesel and plug-in hybrid drivers buy RUC.
Sources: NZTA Waka Kotahi RUC rates and transaction fees (nzta.govt.nz/vehicles/road-user-charges/ruc-rates-and-transaction-fees). Road User Charges Act 2012 (legislation.govt.nz). Fuel excise duty rate per New Zealand government policy.
This calculator provides indicative estimates only based on current NZTA rates for light vehicles (under 3,500 kg) and an approximate fuel excise rate of about 70 cents per litre. It compares road tax only and does not include fuel, charging, insurance or other running costs. Actual costs depend on your driving patterns and vehicle. Check nzta.govt.nz for current rates and to purchase RUC.
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