Warrantywise’s latest Reliability Index, based on analysis of 1.6 million UK repair data points, shows that higher purchase prices in the used car market do not necessarily guarantee better long-term reliability. The findings, covering a three-year dataset of warrantied vehicles, highlight a clear split between dependable small cars and more failure-prone premium SUVs and executive models.

At the top of the rankings is the Toyota Yaris, scoring 89.2/100, reflecting consistently strong reliability and low repair frequency. At the opposite end, the Land Rover Discovery records the lowest score in the study at just 17.2/100, making it the least reliable model in this year’s Index.

The data shows that most of the lowest-scoring vehicles fall within premium segments such as large SUVs and luxury saloons, including models from BMW, Mercedes-Benz, Audi, and Land Rover. Typical reliability scores in this group range between 17 and 28 out of 100, with repairs usually occurring around six to seven years of age and just under 70,000 miles.

Common issues across these vehicles include emissions system faults, electrical problems, and suspension repairs. Average repair costs exceed £2,000, with some models such as the BMW 7 Series and Land Rover Discovery Sport showing particularly high individual repair bills.

Despite their lower reliability scores, these vehicles remain popular due to their comfort, performance, space, and technology. The report notes that complexity in modern premium vehicles—particularly advanced electronics and larger powertrains—may contribute to higher long-term repair risk.

Warrantywise emphasises that reliability is influenced not just by build quality, but also by servicing history, usage patterns, and maintenance. The Index is intended to help used car buyers understand long-term ownership risk rather than predict failure in individual vehicles.

Top 10 Least Reliable Cars In The United Kingdom