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Vehicle finance · net cost of ownership
Auto total cost of ownership, beyond sticker and payment
What a financed car really costs over the years you keep it: down payment, instalments, running costs and any balance left at handover, less its resale value.
Verified engine
What the engine returns
The net total is the headline — what the whole arrangement takes, not what the window sticker said. Read the intermediate figures against it: the level instalment the loan implies, the balance still owed when the car goes, and the operating total. The distance between the net figure and the naive price-less-resale arithmetic is the cost the advertisement never mentioned.
Inputs the result is built from
Purchase price
Down payment
Loan annual rate
Loan term
Payments per year
Annual fuel cost
Annual insurance cost
Annual maintenance cost
Ownership horizon
Residual value at end of ownership
How the result is derived
MethodThe down payment, plus every loan instalment made during ownership, plus the operating costs across the years held, minus the residual value received, plus any loan balance still owed at handover — with the instalment and the balance taken from the closed-form amortisation relation and the zero-rate case handled separately.
StandardComposite total-cost-of-ownership rollup over the standard level-payment amortisation relation
GuardA down payment that equals or exceeds the purchase price is refused — nothing would be financed, and a purchase settled in cash is a different calculation than this rollup.
How the ownership cost moves with the loan rate
Where the money goes in your scenario
Where the sticker price stops and the real cost begins
The advertised price is what the car costs to acquire; the total cost of ownership is what it costs to have. The honest figure counts every amount that leaves because of the car — the down payment, each loan instalment actually made, fuel, insurance and maintenance over the whole holding period — and credits back only the residual value received when the car is sold or traded in.
Inside the rollup sits an ordinary amortising loan. The amount financed is the price less the down payment; the level instalment comes from the quoted annual rate, the term and the payment frequency; and because most people part with a car before the schedule ends, the calculation also derives the balance still owed at handover. That balance does not vanish with the car — it comes due at the sale, and it is where negative equity lives.
The running costs are the quiet half of the total. Fuel, insurance and maintenance are each small beside the price, but they arrive every year of the horizon, and across a typical holding period they can rival the finance side entirely. The monthly payment is the number buyers compare; the running costs are the ones that decide which of two cars was actually cheaper.
The residual value is the only subtraction in the whole account, which is why it deserves a sober estimate rather than a hopeful one. Two offers compared on this page should be compared over the same ownership horizon — the net total is a figure about a stretch of years, not about a car in isolation.
The down payment, plus every loan instalment made during ownership, plus the operating costs across the years held, minus the residual value received, plus any loan balance still owed at handover — with the instalment and the balance taken from the closed-form amortisation relation and the zero-rate case handled separately.
When this calculation is used
- Pricing what a specific car and loan offer will actually take from a budget over the years planned, before signing rather than after.
- Comparing a cheaper car with heavier running costs against a dearer one with lighter, over the same holding period.
- Seeing what selling before the loan ends really costs — the balance that survives the trade-in and comes due at handover.
- Testing a longer loan term honestly: the instalment falls, and this page shows what the larger balance left at sale time does to the total.
- Putting the fuel, insurance and maintenance estimates into the same account as the finance, instead of judging the deal on the payment alone.
Worked example
An ordinary financed purchase: a mid-range car with a modest down payment, a loan running a little longer than the planned years of ownership, typical yearly fuel, insurance and maintenance, and a realistic resale value at handover.
The net total is the headline — what the whole arrangement takes, not what the window sticker said. Read the intermediate figures against it: the level instalment the loan implies, the balance still owed when the car goes, and the operating total. The distance between the net figure and the naive price-less-resale arithmetic is the cost the advertisement never mentioned.
Now stretch the loan term and re-run. The instalment falls, the payment looks kinder — and the balance owed at handover grows, so the net total gets worse. That trade, a friendlier monthly number bought with a worse honest total, is the pattern this whole cluster of pages exists to expose.
What each input represents
Purchase price
The agreed price of the vehicle — the figure the deal is signed at, not the list price before negotiation. Taxes or fees rolled into the financed amount belong here; costs paid separately belong in the running-cost inputs or nowhere.
Down payment
Cash paid at signing. It reduces the amount financed, but it is not a saving — it is the first outflow of the whole account, and it appears in the total on the same footing as every instalment that follows. It must be less than the price, or nothing is financed.
Loan annual rate
The nominal annual rate on the financing, as quoted. It is divided by the payments per year to get the periodic rate the schedule actually uses. Zero is permitted and models a promotional interest-free deal — the instalment then divides the financed amount evenly.
Loan term
How long the loan runs, in years. A longer term buys a smaller instalment and leaves a larger balance owing at any given handover date — the trade this page exists to price. The ownership horizon below may not exceed it.
Payments per year
How many instalments fall in a year; monthly is the convention nearly every auto quote assumes and is the default. It drives both the periodic rate and the count of payments made during ownership.
Annual fuel cost
What a year of driving costs in fuel or charging, estimated from real mileage rather than the brochure figure. It is applied flat across every year of the horizon, so an honest average matters more than a precise first year.
Annual insurance cost
The yearly premium for insuring this car. Premiums differ sharply between models that carry the same sticker price, which is exactly why the figure belongs inside the total rather than beside it.
Annual maintenance cost
Servicing, tyres and repairs, averaged to a yearly figure. Real maintenance grows as a car ages; the rollup applies one flat figure, so an average over the whole horizon is the honest entry, not the first cheap year.
Ownership horizon
How long the car is kept, in years. It sets how many instalments are made, how many years of running costs accrue, and where on the loan schedule the handover lands. It may not exceed the loan term — this rollup assumes the schedule is still running when the car goes.
Residual value at end of ownership
What the car returns at the end — trade-in or private sale. It is the only credit in the account, so an optimistic figure here flatters the whole total; a conservative one biases the comparison in the safer direction.
Assumptions and limits
- The loan rate is fixed for the term, the instalments are level, and the periodic rate is the annual rate divided by the payments per year — a nominal convention.
- Fuel, insurance and maintenance are flat per year across the horizon; real running costs drift with prices and grow as a car ages.
- Taxes, registration, parking, tolls, financing fees and early-settlement charges are not modelled; the balance at handover is the clean closed-form figure.
- The residual value is the estimate entered, not a prediction — the market at handover decides the real one.
- Amounts are not time-discounted: money paid in a later year counts the same as money paid at signing.
What the guards protect against
- A down payment that equals or exceeds the purchase price is refused — nothing would be financed, and a purchase settled in cash is a different calculation than this rollup.
- An ownership horizon longer than the loan term is refused. The rollup assumes the schedule is still running when the car goes; past the final instalment the payment stream ends, and pretending otherwise would misstate the cost.
- A zero or negative purchase price is refused — there is no vehicle to cost.
- The loan term and the ownership horizon must each be a positive stretch of years, and the payments per year must be at least one, so the payment count is a real count.
- The rate, the running costs and the residual value are each bounded to realistic ranges; a figure outside them is refused rather than answered, because the result would not describe any ownership that exists.
Provenance
Composite total-cost-of-ownership rollup over the standard level-payment amortisation relation
The down payment, plus every loan instalment made during ownership, plus the operating costs across the years held, minus the residual value received, plus any loan balance still owed at handover — with the instalment and the balance taken from the closed-form amortisation relation and the zero-rate case handled separately.
Educational reference, not financial advice, and not a substitute for a lender’s settlement figure or a dealer’s quote. The signed pack carries its own citation; the page reports the verification state of the release it mounted rather than asserting one.