Car costs: test depreciation, repairs and charging

Explore uncertainty before treating an estimate as a budget.

Change one assumption at a time

A cost comparison is sensitive to what you type. Keep the period and mileage fixed while changing resale value, then try an unexpected repair separately. These are stress tests, not forecasts or probabilities.

A simple resale-value test

If a retained car is worth £3,000 less after 48 months, its estimated cost rises by £3,000, or £62.50 per month averaged across the period. This does not change the monthly finance bill. When a PCP car is returned normally, the tool does not credit a resale value, so this stress test does not change that scenario.

Repairs and warranties

Use a maintenance estimate that reflects age, mileage and service history, then add a one-off repair stress amount. A repair allowance is money you might spend, not an inevitable charge. Enter warranty premiums separately and check exclusions before assuming repairs are covered.

Electric driving depends on where you charge

The calculator combines home and public electricity prices using your charging share. Consumption is entered in kWh per 100 miles, ideally measured at the charger so losses are reflected. Include installation costs and any additional tariff or parking costs separately. No live tariff or vehicle efficiency data is supplied.

Hybrids need realistic figures

For a plug-in hybrid, enter fuel economy and electricity consumption measured across the same total distance. The tool adds both costs. Do not use petrol-only mileage and electric-only mileage efficiencies as though both apply to every mile. A conventional hybrid can use fuel-only mode.

What the totals exclude

The model does not forecast inflation, future tax changes, investment returns on cash, legal remedies or credit eligibility. Parking, tolls, clean-air charges, breakdown cover and other costs belong in your additional annual costs. Use actual insurance and vehicle-tax figures; they are not inferred from the car’s age or fuel type.

UK context · checked 30 October 2026. Sources: MoneyHelper: PCP explained; MoneyHelper: buying a car. Contract terms vary; these are general explanations.