Guide
How to Calculate the Real Cost of Owning a Car
Purchase price is the smaller half. Here is how to price the rest of ownership.
Split the cost into three parts
Ownership costs fall into acquisition, running and depreciation. Acquisition is the purchase price or the loan payments. Running costs are fuel, insurance, servicing, tyres, registration and taxes. Depreciation is the value the vehicle loses while you own it.
Most buyers compare only the first, occasionally the second, and almost never the third — which is often the largest.
Convert everything to a monthly figure
Annual costs such as registration and insurance should be divided by twelve so they sit alongside fuel in one comparable number. Predictable service items can be spread the same way.
A monthly total is what you can honestly test against your budget. An annual total is easy to admire and easy to ignore.
Use cost per kilometre to compare options
Dividing total cost by distance travelled produces a single figure that compares a cheap car driven a lot against an expensive one driven rarely. It also makes individual journeys tangible — a 40 km round trip at 0.55 per kilometre costs about 22, before parking.
Do not forget the small recurring costs
Parking, tolls, cleaning, occasional fines and the extras added at service time are individually minor and collectively significant. Include them in maintenance rather than pretending they are one-offs.
Frequently asked questions
Is depreciation really that large?
Often the largest single cost of ownership, especially in the first few years. A vehicle you resell costs less in reality than a five-year total suggests, which is why this calculator excludes it rather than guessing a resale value.
Should I include loan interest?
If you are financing, use the Loan Calculator to find the monthly payment and enter that instead of the purchase price. Interest is a real ownership cost.
Why use cost per kilometre?
It compares vehicles used at different intensities on a single scale, and it makes the cost of an individual trip tangible — useful for deciding whether a journey is worth driving.
Conclusion
Purchase price is the smaller half of ownership. Convert every cost to a monthly figure, use cost per kilometre to compare options, and include the small recurring costs that are easy to dismiss and expensive to ignore.