Britain's Best-Selling Cars of 2021

The Reliability Reality Check Five Years On

Posted on Jul 20, 2026

Data analysis by vehicle ownership experts, MotorEasy, reveals that millions of car buyers could be considering purchasing one of the UK’s most popular cars without realising it has a poor long-term dependability record.  Of the top ten models that dominated the new car sales charts in 2021^*, the VW Golf, MINI Hatch and Nissan Qashqai are today ranked among some of the least reliable by the MotorEasy Reliability Index.

In 2021, ten models dominated the new car sales charts, shifting a combined total of over 313,000 units, with the VW Golf, MINI Hatch and Nissan Qashqai accounting for over 91,000 sales. When bought new, those cars would have been covered by a manufacturer warranty providing peace of mind against unexpected repair bills. For most 2021-registered cars, that cover has now expired or is about to. It is precisely at this point, as vehicles age and accumulated mileage takes its toll, that a car’s underlying reliability record begins to matter most to their owners.

The concern is not limited to those three models. Other 2021 best-sellers also rank towards the lower end of the MotorEasy Reliability Index, including the Ford Focus (235th), Nissan Juke (233rd) and Audi A3 (255th) out of 366 models assessed. Together, these three vehicles accounted for a further 63,000 new registrations in 2021, meaning a significant number of motorists could soon be driving cars with below-average long-term reliability as manufacturer warranties come to an end.

MotorEasy has cross-referenced the top ten best-selling cars of 2021 against its MotorEasy Reliability Index to see where they sit today. The index scores are calculated using real-world, real-time, claims data and features 366 makes and models across 47 makes. The analysis includes vehicles between two and 15 years old and represents more than 200,000 years’ worth of warranty claims and repair records.

By evaluating average repair costs and repair frequency, it provides an accurate and comprehensive picture of each model's dependability. The higher the ranking, the poorer the reliability. The findings make compelling reading for used car buyers, current owners, and anyone considering an extended warranty.

At the opposite end of the 2021 reliability spectrum, the picture is very different. The Toyota Yaris, ranks #49 in the MotorEasy Reliability Index and is one of the more affordable cars on the list. This demonstrates that high sales volume and strong reliability are not mutually exclusive. The Ford Puma (#73) and Mercedes-Benz A-Class (#82) also performed considerably better than the bottom three.

The comparison also reveals how reliability can change over time. Of the ten best-selling cars in 2021, only one model - the Mercedes-Benz A-Class - improved its standing in the MotorEasy Reliability Index, climbing from 165th out of 247 models in 2021 to 82nd out of 366 models in 2025. In contrast, every other model with comparable data slipped down the rankings as vehicles aged and accumulated mileage, highlighting how long-term ownership can expose reliability issues that may not have been apparent when cars were newer.

Duncan McClure Fisher, CEO of Intelligent Motoring and founder of MotorEasy, comments, “Cars registered in 2021 are now approaching or beyond their standard manufacturer warranty period. For owners of a Volkswagen Golf, MINI Hatch or Nissan Qashqai, this is the moment when reliability data becomes directly relevant to household budgets.

“These aren’t fringe or obscure models, they are cars that hundreds of thousands of families chose because they trust the badge. But trust alone won’t cover a £4,000 gearbox repair or a failed turbocharger. An extended warranty effectively picks up where the manufacturer leaves off, giving drivers the same financial protection they had from day one and for cars with the reliability profiles we’re seeing in our index, that protection isn’t a luxury, it’s essential.”

The Troublesome Trio: Britain's Least Reliable 2021 Best-Sellers

Volkswagen Golf - MotorEasy Reliability Index #219/366

Despite its reputation for solid German engineering, the Golf's MRI ranking of #219 reflects a model that has become increasingly complex and fault-prone. The most widely reported issues centre on the DSG dual-clutch gearbox, which is known to suffer juddering gear changes, hesitation and transmission failure, typically emerging from around 60,000 miles and a growing catalogue of electrical faults, including freezing touchscreens, dashboard warning lights, central locking failures and malfunctioning driver assistance sensors, problems particularly acute in the Mk8 models bought new in 2021. Diesel variants add DPF blockage to the list, while petrol engines can suffer timing chain wear and high oil consumption. The Golf rewards meticulous maintenance but carries real risk for owners approaching the end of manufacturer warranty.

MINI Hatch – MotorEasy Reliability Index #258/366

The MINI Hatch's MRI ranking of #258 belies its premium appeal. The model's most serious and widely documented fault is timing chain tensioner failure, particularly in R56 and some F56 generation cars, which, if unaddressed, can lead to catastrophic engine damage (BMW issued extended warranties on some affected variants). Alongside this, power steering pump failure has left some drivers with sudden loss of assistance, while electrical faults are a persistent thread: central locking malfunctions, interior lighting failures and infotainment issues are regularly flagged by owners. Water ingress through sunroof seals and door rubbers is a further concern, with damp interiors a common consequence. Annual maintenance costs for an out-of-warranty MINI can run to £800–£1,500, around 50% more than mainstream rivals.

Nissan Qashqai — MotorEasy Reliability Index #259/366

The Qashqai holds the unwanted position of lowest-ranked 2021 best-seller at MRI #259, a reflection of a reliability record that has long troubled independent analysts. The most costly recurring fault is turbocharger failure on diesel and 1.2-litre petrol engines - a repair costing around £1500 plus labour - while battery weakness causes stop-start systems and electronic handbrakes to fail prematurely. Water leaking through the windscreen is a documented and widespread issue, risking electrical short circuits and mould growth under carpets. CVT automatic gearbox variants develop jerky acceleration and overheating faults, often from 40,000 miles, while rear shock absorbers wear prematurely and dashboard rattles are a common complaint. The second-generation Qashqai (2014–2021, the version on sale in 2021) scored just 83.2% in the What Car? Reliability Survey, finishing 19th out of 34 family SUVs.