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Is my car worth fixing?
Under half the car’s value, usually yes. Over the whole value, usually no. In between is where most people actually are, and where the quote in your hand is not the whole bill. This page adds the rest.
Run my numbersIndependent garage pricesDVSA advisory dataVerdict in a minute
A car is usually worth fixing when the total bill, the repair you are facing plus whatever its MOT history says is coming, is under half its market value; above the car’s whole value, selling as-is or scrapping wins. Most drivers never get as far as the sum: according to DVSA MOT data analysed by PriceMyRepair, 38.0% of advisories on cars over twelve years old are never repaired at all.
Run your numbers: the repair, and what is queued behind it
Three steps. The third is the one everyone skips, and the one that changes the answer.
A guess within £500 is fine. Check a free valuation site if unsure.
Advisories on your last MOT certificate optional, but this is the part that matters
Each advisory is weighted by how often that exact wording fails at the next test, from DVSA records, times its repair cost. Not on the list? Our advisory decoder covers seventy.
Fix it
Verdicts use the mid-range independent price; dealer prices run about 50% higher. Advisory costs are expected values, not bills: a 10% chance of a £200 repair counts as £20. Price ranges are estimates and final quotes come from garages. We may earn a commission when you book through our partners, at no cost to you.
Compare quotes from local garagesKeep it, or replace it: the same money, two ways
The 50% rule compares a repair with a car. The better comparison is a year of keeping this car with a year of owning the next one, because that is the choice you are actually making.
Keep = the repair above, the expected cost of your ticked advisories, this year’s service and, as a signal rather than a cost, what you spent in the last twelve months. Replace = the value your replacement loses in its first year at the rate you chose, plus 10% of its price for dealer margin and the friction of changing cars. It leaves out what the replacement will itself need, which nobody can price in advance and which a used car nearly always has. The repairs you are paying for now are the ones you can see.
Five questions, one verdict
The maths above assumes the diagnosis is right and the rest of the car is sound. These five questions check that.
The 50% rule, explained properly
The rule is simple: when a single repair costs more than half what your car is worth, the maths starts working against you. A £1,200 head gasket on a £2,000 car means spending 60% of the car’s value to keep it, and the car is not worth £1,200 more afterwards. Buyers pay for the car, not for its receipts.
Below 30%, fixing is nearly always right. Replacing a car costs more than people budget for: dealer margin, an unknown history, and often its own looming repairs. The car you own is the car you know.
The rule breaks at the edges. A cambelt on a £1,400 runabout can breach 50% and still be worth doing, because the alternative is a destroyed engine. And a £700 repair on a car that also carries three advisories is not a £700 decision. That is why the calculator asks about the certificate.
Five drivers, five verdicts
Independent-garage mid-range prices. Same repair, different car value, different answer.
| Scenario | Car value | Typical bill | Bill vs value | Verdict |
|---|---|---|---|---|
| Clutch kit on a family hatchback | £4,500 | £600 | 13% | Fix it, easy decision |
| Cambelt on an older supermini | £1,800 | £520 | 29% | Fix it, prevention beats a destroyed engine |
| Clutch and DMF on a diesel estate | £2,400 | £870 | 36% | Fix, but shop the price hard |
| Head gasket on a high-mileage supermini | £1,500 | £960 | 64% | Think hard: only with a clean diagnosis and plans to keep it |
| Automatic gearbox on an ageing crossover | £1,200 | £1,500 | 125% | Do not pay this: sell as-is or scrap |
Dealer quotes run roughly 50% higher, which can flip a verdict on its own. That is an argument for comparing quotes, not for skipping the repair.
The repairs that trigger this question
| Repair | Typical range, independent | Why it is a verdict-maker | Full price guide |
|---|---|---|---|
| Head gasket | £520–£1,400 | Labour-heavy; often appears on older, lower-value cars | Head gasket costs |
| Gearbox, major repair | £500–£2,500 | Widest range of any repair; diagnosis quality decides everything | Gearbox repair costs |
| Clutch and flywheel (DMF) | £650–£1,090 | The DMF add-on nearly doubles a clutch bill | Clutch and DMF costs |
| Clutch kit | £450–£750 | Common on cars old enough to be worth little | Clutch costs |
| Turbo, reconditioned | £550–£1,300 | Often quoted new when a recon, or a split pipe, would do | Turbo costs |
| Cambelt kit | £280–£750 | Preventive; skipping it turns into an engine bill | Cambelt costs |
16.0%
of suspension arm ball joint advisories fail at the next test. A queued bill with a probability attached, and the calculator counts it
38.0%
of advisories on cars over twelve years old are never repaired. The decision on this page is one most owners make by not making it
£300+
the usual spread between garages for the same four-figure job on the same car. Comparing quotes moves the verdict more than agonising does
When fixing is the right call
The fault is discrete and the rest of the car is sound. One failed component on a car with a clean advisory history and no structural rust is the best case for repairing. A clutch is a wear item, not a verdict on the car.
The repair buys years, not months. A new cambelt resets a five-year clock. A reconditioned gearbox carries a warranty and usually outlasts it. Compare that with the same money on a slightly newer car of unknown history, with its own cambelt due.
You would struggle to replace it for the money. If your car would fetch £1,500 and the repair is £700, the replacement budget is £2,200 and that is the riskiest end of the used market. Fixing a known car beats buying an unknown one more often than the raw percentage suggests.
When to walk away, and the sunk cost trap
The total exceeds the car’s value. A £1,500 gearbox on a £1,200 car means you could buy the same car, working, for less than the repair. The only exceptions are genuine rarities and real sentimental value, and then decide knowing you are paying for attachment.
This repair is one of a queue. Three advisories waiting their turn mean the real bill is the sum. The advisory decoder gives the odds for each one; the calculator above adds them up.
You are chasing money already spent. Money spent last month is gone whatever you decide today. The only question is whether the next pound is better spent on this car or a different one. Three big bills in a year is the car telling you something, which is why the keep-or-replace calculator asks.
If you do not fix it: scrap, sell as-is, or part-exchange
A “do not fix” verdict is not the end. A broken car still has three routes to money, and they pay very differently. Scrap value is a floor, not a target.
| Route | What you typically get | Effort | Best when |
|---|---|---|---|
| Scrap, authorised treatment facility | A few hundred pounds, by weight | Lowest: collected, paperwork simple | Car does not run, or the bill dwarfs its value |
| Sell as-is, “spares or repair” | Usually well above scrap | Medium: honest listing, time-wasters | Car runs; the fault is known and stated |
| Part-exchange with the fault declared | Trade value minus the repair, roughly | Low: the dealer handles everything | You are buying your next car anyway |
| Fix, then sell | Rarely recovers the repair cost | Highest: you fund the repair first | Cheap cosmetic fixes only |
Scrapping must go through an authorised treatment facility, payment by bank transfer (cash for scrap cars is illegal in England and Wales), and you must tell DVLA. Selling as-is, you must honestly describe faults you know about; “sold as seen” does not license hiding a dead gearbox.
Before you decide anything: is the diagnosis even right?
The worth-fixing maths is only as good as the diagnosis feeding it, and the most expensive repairs have cheap impersonators. A head gasket that was never block-tested might be a thermostat. A failing turbo is a split boost pipe surprisingly often. A gearbox on its way out can be a clutch cable or low oil. Ask the garage what test confirmed it and whether you can see the result. A garage confident in its diagnosis will show you.
For any bill that fails the 50% test, a second opinion costs an hour of diagnostic time and can save four figures. If the diagnosis stands, you have two quotes instead of one.
Frequently asked questions
How do I know if my car is worth fixing?
Compare the repair bill to your car's market value: under 50% of value, fixing usually wins; over 100%, selling or scrapping wins. Between the two, it depends on the car's overall condition, what else is queued on its MOT history, and how long you plan to keep it. Run the numbers in the calculator above, including the advisories on your certificate, not just the quote in your hand.
What is the 50% rule for car repairs?
The 50% rule says a repair costing more than half your car's value deserves serious hesitation, because the repair does not add its cost back to the car's worth. It is a threshold for thinking, not an automatic no: preventive jobs like cambelts and discrete faults on otherwise sound cars can justify crossing it.
Should I count MOT advisories in the decision?
Yes, and most people do not. An advisory is next year's bill with a probability attached. According to DVSA MOT data analysed by PriceMyRepair, a suspension arm ball joint with slight play fails on the same joint at the next test 16.0% of the time, while an oil leak that is not excessive fails 1.2%. Tick your advisories in the calculator and the expected cost is added to the repair you are facing.
Should I fix my car or scrap it?
Scrap only when the car does not run and the repair costs more than the car is worth; scrap yards pay by weight regardless of the model. A car that starts and drives is nearly always worth more sold as-is with the fault declared. Fix it when the total bill, including what is queued, is under half the car's value and the rest of the car is sound.
Is it cheaper to keep an old car running or buy a newer one?
Keeping a paid-off car running is usually cheaper per year. A replacement bought for a few thousand pounds loses a slice of that in its first year, carries a dealer margin, and arrives with its own deferred maintenance. The keep-or-replace calculator above puts the two side by side for your numbers. The balance tips when repairs become frequent rather than occasional, or when a single bill exceeds the car's value.
Is it worth fixing a head gasket?
A head gasket typically costs £520–£1,400 at an independent garage, so on cars worth under £2,000 it often fails the 50% test. Before deciding anything, insist on a block test: overheating and coolant loss have cheaper causes, and paying four figures on a guessed diagnosis is the real mistake.
Is it worth repairing a gearbox?
Gearbox bills run £500–£2,500 depending on whether it needs a repair, a rebuild or a replacement, the widest range of any common repair. On a car worth £3,000 or more, a reconditioned unit with a warranty usually makes sense. Rule out cheap causes first: low oil, a worn clutch, or a sensor can mimic gearbox failure.
Should I repair my car before selling it?
Mechanical repairs rarely pay back at sale; a £700 clutch might add £300 to the price. Cheap, visible fixes are different: a bulb, a tyre or a fresh MOT can add more than they cost because they remove buyer objections. Fix what is cheap and visible; declare what is expensive and mechanical.
Can I sell a car that needs repairs?
Yes. Listing it as spares or repair with the fault honestly described is legal and common, and typically pays well above scrap value. You must not misrepresent faults you know about, and if the car is dangerous to drive you should say so and expect the buyer to collect it by trailer.
How much do you get for scrapping a car in the UK?
Typically a few hundred pounds, driven by the car's weight and current scrap metal prices rather than its model or condition. It must go through an authorised treatment facility, payment must be by bank transfer, since cash for scrap cars is illegal in England and Wales, and you must tell DVLA or risk a fine.
What is the sunk cost trap with car repairs?
Spending money on a car because you have already spent money on it. Last month's £800 is gone whatever you decide today; the only question is whether the next pound is better spent on this car or a different one. If this is the third significant bill in a year, that pattern is data, and the calculator has a field for it.
Is it worth fixing a car that failed its MOT?
Usually yes. Most MOT failures are routine items like brakes, tyres, suspension and lights costing far less than people fear. It stops being worth it when the failure list is long and structural, such as corrosion or several suspension components, on a low-value car. Price the full list, then apply the 50% test to the total.