The average cost of owning a car can’t be reduced to one useful figure without knowing the vehicle, how far it will be driven, how it’s financed and how long it will be kept. A realistic estimate includes depreciation, interest and fees, insurance, fuel or electricity, servicing, repairs, vehicle licensing, inspections and other running costs. For a New Zealand buyer, costs such as a Warrant of Fitness (WOF) and Road User Charges (RUC), where applicable, also belong in the calculation. Compare the same ownership period and annual distance for each vehicle, then turn the total into a monthly budget.
Two people can buy the same model and face very different bills. One may drive short local trips and pay cash; another may travel long distances, finance the purchase and park in an area where insurance costs more. Vehicle age, condition, fuel type, repair history and resale value also change the result.
That’s why a headline average may not describe what a particular car will cost you. Treat estimates as comparisons, not promises. Before deciding, calculate costs for your expected ownership period and use your own driving pattern, finance terms and insurance quotes.
It also helps to keep two questions separate: “Can I afford the payments and bills as they fall due?” and “How much value will I use up by owning this car?” The first is about cash flow; the second is about the car’s total cost of ownership.
Depreciation is the difference between what you pay for a car and what you can sell it for later. It is a real ownership cost even though you don’t usually pay it as a separate bill. Estimate a likely resale value for the end of your planned ownership period, rather than assuming you’ll recover the purchase price.
Resale value is uncertain. Condition, mileage, service records, demand and the vehicle’s history can all affect what a buyer will pay. Compare similar vehicles and use a cautious estimate. If your budget only works when you achieve an optimistic sale price, the purchase may be too risky.
If you borrow to buy, include the interest and any loan fees. Check the amount borrowed, rate, term, fees, repayment schedule and any final or balloon payment. A lower regular repayment can make a car seem affordable while a longer loan term increases the total interest you pay.
Don’t confuse the loan balance with the car’s ownership cost. The principal repays money used to buy an asset; interest and fees are additional costs. How to account for principal depends on whether you’re planning monthly cash flow or comparing the total economic cost, as the table below explains.
Get an insurance quote for the specific car before you commit. Premiums can depend on factors such as the vehicle, where it is kept, how it is used, the driver’s circumstances and the policy excess. A quote for a similar model may not be a reliable substitute.
Compare the cover as well as the premium. Check the excess, exclusions, how the insurer values the car after a loss, and whether the policy fits your circumstances. A cheaper policy may leave you responsible for more of the cost after an accident or theft.
Estimate energy costs from the distance you expect to drive and the vehicle’s consumption. For a petrol or diesel vehicle, a useful calculation is:
Annual fuel cost = annual kilometres ÷ 100 × fuel use per 100 kilometres × price per litre
Use a realistic consumption figure for the exact vehicle where possible, and consider the mix of driving you’ll actually do. Traffic, short trips, load and driving style can make real-world consumption differ from a published figure. For an electric vehicle, estimate electricity use and the cost of the charging you expect to do, including any public charging you regularly rely on.
Regular servicing and wear items are different from unexpected repairs, so budget for both. Check the manufacturer’s maintenance schedule and the vehicle’s service history. For a used car, an independent pre-purchase inspection can help identify work that may be due or faults that could affect the budget.
Set aside a repair reserve that reflects the car’s age, condition and known maintenance needs. There is no single reserve that suits every vehicle. A car with incomplete records or an inspection that identifies upcoming work calls for more caution than one with a clear history and no immediate concerns.
In New Zealand, include vehicle licensing costs, commonly referred to as “rego,” and allow for WOF inspections and any work needed to address inspection findings. An inspection fee does not cover repairs. Some vehicles are also subject to RUC; whether it applies and what you owe depend on the vehicle and current rules, so confirm the position for the exact vehicle with the New Zealand Transport Agency (NZTA).
Also account for costs that are easy to overlook: tyres, parking, tolls, roadside assistance, cleaning and accessories. Include only expenses that apply to your situation, but don’t leave out regular costs simply because they aren’t part of the purchase transaction.
Use a cash-flow budget to check whether you can meet bills as they arrive. Use a total-cost estimate to compare the financial cost of owning one vehicle with another. Keeping the two methods distinct prevents double-counting the loan principal.
| Approach | What to include | Best used for | Common mistake |
|---|---|---|---|
| Cash-flow budget | Deposit, loan repayments, running costs and eventual sale proceeds | Checking whether payments and bills fit your monthly budget | Forgetting irregular expenses such as repairs, tyres or inspections |
| Total cost of ownership | Purchase price minus resale value, plus interest, fees and running costs | Comparing the overall cost of keeping different vehicles for the same period | Adding loan principal on top of the purchase price less resale value |
For a quick comparison, estimate the total cost over your planned ownership period, then divide by the number of months. If you want to compare vehicles used for different distances, calculate an estimated cost per kilometre as well. These figures are planning tools, not guarantees: repairs and resale proceeds can differ from your estimates.
For a more useful decision, prepare a cautious and a more favourable estimate for each vehicle. If the car only fits your budget under the favourable assumptions, consider a less expensive option or delay the purchase.
Compare cars that could genuinely meet the same needs. A lower purchase price can be offset by higher fuel use, deferred maintenance or a weaker resale estimate. A more expensive vehicle may have lower running costs, but that doesn’t automatically make it the better-value choice once financing and depreciation are included.
New and used cars require different checks. A new car’s purchase price and expected resale value may make depreciation a major part of the estimate. With a used car, condition and maintenance history deserve close attention because repairs could disrupt both your budget and your plans. Neither option is always cheaper overall; compare the specific vehicles over the same period.
Fuel type matters too. An electric vehicle’s energy costs depend on its consumption and where you charge it, while a petrol or diesel vehicle’s fuel bill depends on its use and fuel prices. Compare energy, purchase price, finance, insurance, maintenance and resale together rather than choosing on one running-cost estimate alone.
A useful estimate includes depreciation, finance interest and fees, insurance, fuel or electricity, servicing, repairs, tyres, licensing and other costs that apply to your use. The purchase price alone doesn’t show what the car will cost over the period you own it.
Include repayments when checking cash flow, because they are money you must pay on schedule. For an economic ownership-cost comparison, count the purchase price less resale value, then add interest and fees; don’t add loan principal again on top of the purchase price.
Estimate your annual distance, find a realistic consumption figure for the specific vehicle, and apply the fuel-price assumption you want to use. Since actual consumption and fuel prices can change, test more than one scenario if the result is close to your budget limit.
No. A lower purchase price may help, but repairs, maintenance needs, insurance and resale value affect the full calculation. Compare the condition and likely costs of the specific used car with those of the alternatives you’re considering.
Allow for vehicle licensing and WOF-related costs, and confirm whether the specific vehicle is subject to RUC under current rules. Keep inspection costs separate from any repairs needed after an inspection.
The average cost of owning a car is most useful when it reflects your vehicle, driving distance, finance terms and likely resale value. Build estimates for those items before buying, compare cars over the same period, and make sure the monthly budget still leaves room for repairs and other irregular costs.
