The purchase price is the cheapest honest number ever attached to a car. Everything after it is a slow leak: fuel, insurance, tax, tyres, the service that always finds one more thing. If you've never sat down and built a car running costs budget, that leak is almost certainly wider than you'd guess, and it tends to show up as a vague feeling that your money evaporates faster than your spending explains.
This isn't an argument for selling the car. For plenty of people it isn't optional, and the bus doesn't go where they work. But there's a real difference between paying what a car costs and being ambushed by what a car costs. The second one is expensive in ways that have nothing to do with the car.
The car costs people remember, and the ones they don't
Ask someone what their car costs and you'll get fuel, then insurance if they've thought about it for a second. Both are real. Neither is usually the full picture, because the expensive stuff arrives once a year and gets filed in your head as bad luck rather than as a cost.
Here's the fuller list, roughly in the order people forget it:
- Fuel or charging. The one you track, because you pay it weekly and it hurts in small, memorable increments.
- Insurance. Annual, big, and repriced every renewal whether anything about you changed or not.
- Tax, registration and the annual test. Compulsory, and easy to forget about until the letter lands.
- Servicing. The quoted price is the floor. The invoice is the price plus whatever they found while it was on the lift.
- Tyres and brakes. Not annual, which is why they feel like disasters. Tyres last a few years, so a set is really a monthly cost you've been quietly deferring.
- Parking, tolls and fines. Small, frequent, almost never counted. Add up a year of them before you dismiss this one.
- Depreciation. The largest cost for most newer cars and the only one that never sends an invoice.
How to build a car running costs budget from your own numbers
Skip the online calculators. They're built on national averages, and averages are useless here because the spread is enormous. A ten year old runabout and a three year old SUV are not the same animal, and your insurance premium depends on things no calculator knows about you.
Pull your last twelve months instead. Go through statements and write down every payment connected to the car, with the month it landed. You want actual amounts, not remembered ones, because memory rounds everything down. Then do the only sum that matters: add the year up and divide by twelve.
Say you land on $1,400 insurance, $300 tax and test, $480 servicing, $600 on a set of tyres spread over three years so $200 a year, $2,100 fuel and about $250 of parking you'd never have guessed. That's $4,730, or roughly $394 a month. The fuel you were tracking is well under half of it.
Almost everyone who does this arithmetic for the first time comes out with a number they'd have called ridiculous an hour earlier.
That monthly figure is the useful output. It tells you what the car genuinely takes out of your month, it gives you something to set aside before the renewals arrive, and it lets you compare the car honestly against the alternative rather than against a hazy sense of fuel costs.
Depreciation, the bill that never arrives
Depreciation is the gap between what you paid and what the car is worth now, and it's invisible because nobody ever asks you to pay it. You pay it all at once, later, in the form of a resale figure that's lower than you'd pictured.
You can measure it in five minutes. Look up what your model, year and mileage sells for today, and compare it to the same lookup a year ago. No previous lookup? Then take what you paid, subtract today's value, and divide by the years you've owned it. That's your annual depreciation, and on a reasonably new car it can comfortably beat your fuel bill.
Two things follow from that. One, a cheaper used car can cost less to own even when it costs more to keep running, because most of its depreciation already happened to someone else. Two, if you're comparing cars, the sticker price difference is a bad guide to the ownership cost difference. The slower depreciating car is sometimes the more expensive one to buy.
How to track fuel, parking and the small stuff without giving up
The annual costs are easy to budget for once you know them. The daily spending is where car budgets actually fall apart. Fuel, parking meters, the car wash, a bag of screenwash, tolls. Individually trivial, collectively a few hundred a year, and almost impossible to reconstruct later from a statement that just says the name of a forecourt.
What works is logging it in the moment, which means the logging has to take seconds rather than minutes. Two habits make the difference:
- Log at the pump or the meter, before you drive off. Thirty seconds later you're thinking about something else and it's gone.
- Keep one category called Car rather than six. You want to answer "what did the car cost last month", and you don't need to split screenwash from a car wash to do that.
This is where an app earns its keep. Logging a spend in Bud takes about seven seconds, and on iPhone you can wire it to the Action Button so it's one press while you're still standing at the pump. There's no bank login involved, so nothing waits on a card payment to settle before you can see it. Buddy, the assistant inside the app, will answer the question directly: ask what you've spent on the car this year and you get a figure back rather than a chart to squint at. Bud is free to download, and Bud Plus is $1.99 a month or $15.99 a year.
What to do once you know the number
Three honest options, and only one of them is dramatic.
Fund it properly. Take the monthly figure and move it somewhere the moment you get paid. The annual bills stop being events because the money was already labelled for them.
Attack the controllable lines. Insurance is worth shopping every single renewal, because loyalty is reliably punished. Servicing at an independent garage usually costs less than the dealer. Those two are where most of the easy savings live.
Question the car. If it's eating a large slice of your income and you drive it twice a week, the arithmetic might be telling you something. Price out what those journeys would cost by train, taxi or an occasional rental. Sometimes it's cheaper and sometimes it really isn't, but you only find out by comparing a real number to a real number.
How often to redo this
Once a year, around your insurance renewal, since the figure you need most has just landed in your inbox. Twenty minutes to redo the sum and glance at the depreciation is plenty. Costs drift, cars get older and need more, and premiums climb for reasons nobody explains.
Nothing about this makes the car cheaper. What it does is move the cost from a thing that happens to you into a thing you planned for, and that's a much bigger upgrade to your month than it sounds.
Track your money in seconds, not spreadsheets.
Bud is free to download, built for iPhone, and never asks for a bank login.
