What the family car really costs: every item, not just fuel
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Ask a family how much they spend on the car and the answer is almost always the same: filling up. But fuel is only part, often less than half, of the real cost. The rest comes once or twice a year — insurance, road tax, the service, tyres — and so gets forgotten when doing the sums.
Knowing what the car really costs helps you decide better: whether to keep it, replace it, or whether a second car is essential.
This article is about organisation, not financial advice.
The cost items
Fixed costs (even if the car stays parked)
- insurance, third-party and any extra cover
- road tax
- periodic inspection
- garage or parking space, if you pay for one
- finance or lease payments, if any
Variable costs (linked to use)
- fuel or electric charging
- tolls and parking
- car washes
Maintenance
- services as per the handbook
- tyres: seasonal changes, replacement for wear
- brakes, battery, filters
- unexpected repairs
The hidden cost: depreciation
A car loses value every year, especially in the first few. It isn't a bill you pay, but it's money going: when you sell, you'll get much less than you paid.
Keeping track without effort
Deadlines and jobs on the record
In KidBox's Vehicles section each car has its record with road tax, insurance and inspection deadlines, and a history of jobs — service, tyres, brake pads, repairs — with date, mileage and cost. Every job with an amount automatically becomes an entry in family expenses, under the car's category. Nothing written twice.
Everything else in expenses
Fuel, tolls, parking and washes go into expenses under the same category. For fuel, if recording every fill-up is too much, monthly totals from the card you use are enough.
The annual summary
After a year, the expense summary by category shows the car's total cost. Dividing it by miles driven gives the cost per mile: a very useful number for comparing alternatives — a smaller car, public transport for the commute, car sharing instead of a second car.
With two cars
In two-car families it's worth keeping records and expenses separate per vehicle: you often discover that the second car, used little, costs a lot per mile because of fixed costs. It helps decide whether it's really needed. More in two cars in one family.
Before buying
Before buying a car, estimate every item — not just the price or monthly payment — for the model you have in mind: an insurance quote, road tax, fuel consumption, service costs. Two cars at the same price can have very different annual costs.
In short
Fixed costs, variable costs, maintenance and depreciation: fuel is only part of it. Deadlines and jobs on the vehicle record, becoming expenses automatically, everything else in expenses under the same category, an annual summary with cost per mile and separate records for each car. The car will cost what it costs. But you'll decide with the real numbers.
The tools this article talks about
Read next
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