Why Vehicle Inspection Pass Rates Vary by Region Even Under the Same Rules

A technical inspection checks whether a vehicle on the road still meets the safety and environmental standards set when the rules were written, covering items such as brakes, lights, tyres, steering, bodywork corrosion and exhaust emissions. In most European systems, inspectors do not grade a car pass or fail on a single scale; they classify each defect found by severity, then decide whether the vehicle can keep driving, needs a quick fix, or must be re-tested.

How the inspection itself is structured

In France, the UTAC-OTC, the national technical body designated to oversee the contrôle technique, sorts findings into minor, major and critical defects. A major defect forces the owner to repair the car and return for a free re-test, called a contre-visite, within roughly two months; a critical defect can mean the vehicle is barred from driving the same day except to go straight to a garage, according to UTAC-OTC data reported by L'Argus.

That classification system is identical whether the inspection takes place in Paris or in rural Brittany. What differs is how many vehicles, in each place, actually trigger a major or critical finding — and that is where the regional gap opens up.

France: a national average that hides a wide regional split

UTAC-OTC's 2025 annual report, summarised by L'Argus, puts the national re-test rate for passenger cars (category M1) at 18.24%, down 0.1 points from 2024. Light commercial vehicles (N1) fail more often, at 22.39%. Across all vehicle categories combined, the re-test rate was 19.30%, essentially unchanged from the previous year, made up of 18.58% major defects and 0.72% critical defects.

Underneath that national figure, the département-level data shows a large spread. Val-d'Oise, near Paris, recorded the lowest re-test rates in the country: 9.78% for passenger cars and 9.87% for light commercial vehicles. Ille-et-Vilaine, in Brittany, had the highest passenger-car re-test rate at 27.65%, and Loire-Atlantique, in Pays de la Loire, topped the light-commercial-vehicle ranking at 33.17%. Yahoo News France, drawing on the same regional pattern, reported that failure rates exceed 25% across several western regions including Brittany and Pays de la Loire, well above the rate seen in the Île-de-France region around Paris.

What explains the gap, according to the data

Both L'Argus and the Yahoo News France report point to the same underlying factors rather than inconsistent enforcement between centres. The French vehicle fleet is ageing: the average passenger car was 13.2 years old in 2025, up from 12.9 the year before, and more than 60% of vehicles presented for inspection were over ten years old, a group that fails at a notably higher rate than newer cars, per UTAC-OTC figures cited by L'Argus. The three most common major defects nationwide involved headlamp alignment, present in 4.77% of inspections, tyre condition or fitting at 3.46%, and emissions-control components at 2.95%.

A technical-centre manager quoted in the Yahoo News France report attributed most failures to simple owner neglect — people arriving for inspection with burnt-out bulbs, misaligned headlights or worn tyres — rather than to any difference in how centres apply the rules. Regions with older vehicle fleets, more rural driving and a higher share of light commercial vehicles therefore show up with higher failure rates, even though inspectors everywhere are working from the same checklist.

Switzerland: when the same country has 26 inspection authorities

France centralises inspection standards under one national technical body, but other countries delegate inspection authority to regional governments, which can make outcomes depend on jurisdiction as much as on the vehicle itself. A dispute over a 1959 Volkswagen, reported by Car Revs Daily, illustrates this in Switzerland, where each canton runs its own vehicle inspection service.

The car, fitted with an engine-mounted compressor that raised its power above its declared specification, failed inspection in Aigle, in the canton of Vaud, in October 2025. Its owner tried to have the re-test carried out in the neighbouring canton of Valais instead, arguing that officials had agreed to it. The Vaud Cantonal Court rejected the appeal, ruling that although a federal directive (ASA Directive No. 17) allows inspections to be transferred between cantons, this is a matter of administrative discretion rather than an enforceable right. The court found no documented approval for the transfer and ordered the owner to pay CHF 800 (about €830) in costs.

The ruling does not change what a Swiss inspection checks, but it confirms that which canton handles a case — and how willing that canton's authority is to accommodate a transfer — can determine the outcome once a vehicle is already flagged as non-compliant.

United Kingdom: pass rates that vary by area

In Britain, the MOT test is run under a single national framework, but an analysis of official DVSA test data by the tyre retailer Black Circles found pass rates varying sharply by postcode area. Over a four-year period (2020-2024), Llandrindod Wells in Wales recorded a 99.09% pass rate, with only 481 failures out of 52,958 tests, while East Central London reached 98.98% and Dorchester 98.90% across 184,622 tests.

Black Circles also reported separate overall MOT failure rates for several Scottish areas: Aberdeen had a 3.91% failure rate across 2020-2024, falling to 3.32% in 2024; Dundee had 3.88% (3.43% in 2024); and Falkirk had 3.54%. Alongside these figures, the company cited UK Department for Transport collision data showing that road-environment factors contributed to 19% of collisions in Falkirk and 12% in those in Aberdeen, compared with 11% in Llandrindod Wells, where no collisions were attributed to a poor or defective road surface. Black Circles presented the two datasets together but did not claim the MOT failure rates themselves were caused by road-surface defects.

The common thread across countries

• Legal checklists and defect thresholds are set at national level, so the rules a driver faces are not what changes between regions.
• Fleet age and vehicle category mix differ by area — older, higher-mileage or more commercial-heavy fleets fail more often, as seen in Brittany and Pays de la Loire.
• Owner maintenance habits vary locally and are cited by French inspection staff as the single biggest driver of avoidable failures.
• Administrative structure matters where inspection authority is decentralised, as the Swiss cantonal case shows.
• In the UK analysis, areas with higher MOT failure rates were also areas where official collision data showed a larger role for road-environment factors, though the source does not establish a causal link between the two figures.

What this means for drivers

None of the sources reviewed suggest that inspection centres in high-failure regions are applying stricter rules than centres elsewhere. Instead, a car's chance of passing depends heavily on its own age and upkeep, and only secondarily on where it happens to be registered or tested. A well-maintained car in a high-failure département or postcode area is still judged against the same national standard as one in a low-failure area.