Mercedes-Benz B-Class vs Vauxhall Zafira
On MOT-testable defects, the Mercedes-Benz B-Class (fail rate 18.2%) performed better than the Vauxhall Zafira (24.2%) across comparable years. The biggest divergence was emissions & environmental, where the Zafira recorded failures more often.
18.2%
B-Class fail rate
24.2%
Zafira fail rate
6.01pp
Difference
Side by side
| Metric | Mercedes-Benz B-Class | Vauxhall Zafira |
|---|---|---|
| MOT tests analysed | 429,942 | 1,459,072 |
| Pass rate | 81.8% | 75.8% |
| Fail rate | 18.2% | 24.2% |
Where they differ
| Category | B-Class | Zafira |
|---|---|---|
| Emissions & environmental | 0.0% | 6.2% |
| Suspension | 6.7% | 10.6% |
| Lighting & signalling | 8.2% | 12.1% |
| Visibility | 3.2% | 0.0% |
| Brakes | 5.0% | 7.4% |
| Tyres | 5.6% | 6.9% |
Methodology & source. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-01. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.