Used Car Complaints Hit a Record High as Nearly 19,000 Buyers Complain

Nearly 7.8 million used cars changed hands in the UK last year, and 18,570 of those buyers went on to file a formal complaint with The Motor Ombudsman, a rise of 14 per cent on the 16,317 complaints logged in 2024. Used cars now account for 40 per cent of every case the ombudsman opens, more than any other category it handles.

Set against the scale of the market, 18,570 complaints looks small: one dispute for every 420 cars sold. But that ratio is moving the wrong way. In 2024 it was one in 468. A used car buyer today is more likely to end up in a formal dispute than a buyer was just twelve months ago, and the reasons behind that shift point squarely at how dealers treat customers once the sale is done, not just what breaks under the bonnet.

Customer service tops the complaints list, again

The single biggest driver of used car disputes in 2025, at 40 per cent, was the level of customer service buyers received from the retailer, either at the point of purchase or afterwards. That covered cars sold with undeclared modifications and undisclosed history, and buyers who contacted a dealer with a question or a problem and simply never got a reply.

Engine and powertrain failures made up 35 per cent of complaints, the biggest mechanical category by some distance. The specific faults reported to the ombudsman included cylinder head bolts shearing, timing tensioner pulleys loosening, cracks forming in engine blocks, oil pumps seizing crankshafts after failing silently, and head gaskets wearing out early on cars with very low mileage. These are not cosmetic niggles. Every one of them is the kind of repair bill that can run into thousands of pounds on a car a buyer had every reason to think was sound.

Exterior faults, among them leaking windscreens letting water into the cabin, tailgates that would not open in cold weather, and rust appearing within weeks of a sale, accounted for a further 5 per cent. Fuel and emissions problems and electrical faults each made up 4 per cent, and tyre and brake defects, including mismatched tyre sizes fitted to the same car, rounded out the top six causes at 3 per cent.

Why buyers are exposed even when they do the right checks

Most buyers already know to run an HPI check for outstanding finance and to look over a service history before handing over money. What the ombudsman’s figures show is that neither of those steps catches the biggest source of complaints: how a dealer behaves after the deal is signed. A vehicle history check does not tell a buyer whether a dealer will answer the phone when a fault turns up in week three, and a service book does not say whether a part-exchange value quoted verbally will still be honoured once the paperwork is drawn up.

That gap counts for a lot: a used car purchase is one of the largest single payments most households make outside a mortgage, and buyers frequently have far less legal protection in mind at the point of sale than they do for almost any other big-ticket purchase. Bill Fennell, Chief Ombudsman and Managing Director of The Motor Ombudsman, said accreditation to the Vehicle Sales Code gives both businesses and buyers an important safety net when something goes wrong, as so many disputes stem from customer service failures that have nothing to do with the mechanical condition of the car.

A big-ticket purchase with surprisingly thin legal awareness

A second-hand car is one of the few purchases in the thousands of pounds that most people make with little more protection in mind than a handshake and a logbook. Compare that with a mortgage, where a buyer expects a survey, a solicitor and a paper trail at every stage, and the gap in how carefully used car purchases are approached becomes obvious. The Motor Ombudsman’s figures suggest that gap is exactly where the newest wave of disputes is opening up.

Warranty coverage disputes sit alongside the mechanical categories rather than as a category of their own, and they follow a familiar pattern: a buyer is told a fault is covered, submits a claim, and then finds the warranty excludes the specific part that failed, or applies a wear-and-tear clause that was never explained at the point of sale. These disputes hinge on the wording of a contract signed weeks or months earlier, which makes them far harder to resolve after the fact than they would have been if the buyer had simply asked to see the exclusions list before signing.

Delays to the supply of parts for repairs have also become a recurring complaint in their own right, with buyers left without a car, and in some cases without a functioning courtesy vehicle, for weeks while a dealer waits on a part. A short, specific question at the point of sale, whether the dealer can guarantee parts availability for known problem areas on that particular model, can flag a risk before it becomes a drawn-out dispute.

What to check before you buy, and what to do if it goes wrong

• Search for the dealer on The Motor Ombudsman’s Business Finder at themotorombudsman.org before you buy. Retailers accredited to the Vehicle Sales Code are bound to resolve disputes through the ombudsman rather than leaving you to take them to small claims court.
• Get every verbal promise confirmed in writing before you pay a deposit, including part-exchange values, agreed faults the dealer says they will fix, and the exact specification of the car.
• Use your rights under the Consumer Rights Act 2015. You can reject a faulty used car within 30 days for a full refund. Between 30 days and six months, the dealer must prove the fault was not present at the point of sale, rather than you having to prove it was.
• Get an independent inspection, especially on cars above ten years old or with an engine known for the faults listed in the ombudsman’s data, such as timing components or head gaskets. An inspection costing a few hundred pounds can save thousands if it catches a fault before you buy.
• If a dealer stops responding to a fault, write a formal letter of complaint referencing the Consumer Rights Act and give them a reasonable window, generally 14 days, to respond before contacting the ombudsman or Trading Standards.
• Keep every text message, email and phone log relating to the purchase. Disputes over undisclosed modifications or unanswered queries are resolved far faster with a clear written trail than with a buyer’s word against a dealer’s.

Buyers who found their car through an online listing and completed the purchase remotely, without visiting a showroom before paying, have additional protection under distance selling rules, including a right to cancel within 14 days in many circumstances. That protection does not automatically apply to a car viewed and bought in person at a dealer’s premises, which makes it worth asking a seller directly, before you pay a deposit, exactly how the sale is being structured.

If a dealer accredited to The Motor Ombudsman’s codes will not resolve a complaint directly, a dispute can be raised free of charge at themotorombudsman.org/consumers/make-a-complaint. For dealers outside the scheme, the Consumer Rights Act and your local Trading Standards service remain the main avenues open to you.

A used car purchase carries real financial exposure long after the keys change hands, and the ombudsman’s own data shows that the retailer’s conduct after the sale, not just the condition of the engine, is now the leading reason buyers end up in a formal dispute. Checking a dealer’s accreditation before you sign anything takes minutes and can save months of argument later.

Sources:

• https://www.themotorombudsman.org/press-releases/tmo-reports-14-rise-in-used-car-disputes-in-2025/
• https://www.themotorombudsman.org/consumers/our-codes-of-practice/vehicle-sales-code/
• https://www.themotorombudsman.org/consumers/make-a-complaint/