Every car in Great Britain over three years old needs an MOT once a year, without exception. It is a legal requirement, not an optional health check, and driving without a valid certificate can mean a fine of up to £1,000. Yet most drivers book the test every twelve months without ever seeing a full breakdown of what a tester actually inspects.
This guide sets out exactly what is checked on an MOT, how long the test takes, what it costs, and what the DVSA’s own pass-rate data says about your chances on the day. If you’re due a test in Worthing, Gleam Tech Auto Ltd is a fully approved MOT testing station offering Class 4 MOTs for cars and light vans.
MOT stands for Ministry of Transport, the government department that originally introduced the test in 1960. Today it is administered by the Driver and Vehicle Standards Agency (DVSA), which sets the inspection standards, licenses testing stations, and audits the data from every test carried out in Great Britain.
The test exists to confirm that a vehicle meets minimum road safety and environmental standards, nothing more. It is not a mechanical health check, and passing an MOT doesn’t mean your car is problem-free; it means the specific items on the DVSA’s checklist met the legal minimum on the day of the test.
Cars, motorcycles and other vehicle types need their first MOT three years from the date they were first registered, then annually after that.
The MOT covers around 20 major inspection areas. Testers work through the vehicle systematically, checking each item against the DVSA’s published inspection manual. Here is what is checked during an MOT test, grouped by system.
The brake system is tested using a rolling road brake tester, which measures the braking force at each wheel. Testers check the handbrake, footbrake, brake pads, discs, and pipework for wear, corrosion or leaks, and confirm the imbalance between left and right wheels falls within DVSA limits.
Every tyre needs at least 1.6mm of tread depth across the central three-quarters of the tread, around the full circumference. Testers also check for cuts, bulges, exposed cord, incorrect tyre size or type, and correct wheel fixing.
Headlights, sidelights, indicators, brake lights, fog lights, and number plate lights are all checked for function, correct colour, security, and aim. A single blown bulb is one of the most common and cheapest reasons for a failure.
Testers check the steering mechanism for excessive play, check power steering fluid and function where fitted, and inspect suspension components including springs, shock absorbers, and joints for wear, corrosion, or damage.
Every seatbelt is checked for correct operation, securing, and condition, including the buckle and the webbing itself for fraying or cuts. Driver and front passenger seats must be securely fixed and adjustable as designed.
Testers look for sharp edges, corrosion near the frame or mounting points that could affect structural integrity, and any bodywork damage that could cause injury.
The exhaust system is checked for leaks, security, and excessive noise, and the vehicle undergoes an emissions test appropriate to its fuel type. Petrol cars are checked for carbon monoxide and hydrocarbon levels; diesel cars are checked for smoke opacity, with stricter checks for vehicles fitted with a diesel particulate filter (DPF).
The windscreen is checked for cracks or chips within the driver’s line of sight, specifically a 290mm-wide zone in front of the driver, where a chip larger than 10mm or a crack longer than 40mm will fail the test. Wipers must clear the screen effectively, and washers must work.
Mirrors must be present, secure, and undamaged. The horn must work and be audible. Number plates must be legible, correctly formatted, and securely fitted.
Testers check for fuel leaks and confirm the fuel cap seals correctly.
The Vehicle Identification Number must be present, legible, and match the vehicle’s registration document.
For the full item-by-item breakdown down to individual component tolerances, our companion guide covers every item on the MOT checklist in tester-level detail.
The MOT deliberately excludes some things drivers often assume are covered. The engine’s internal condition, clutch, gearbox, and general mechanical reliability are not tested, unless a fault directly creates a safety or emissions issue. A car can pass its MOT and still need significant mechanical work; the test is a safety and environmental floor, not a full inspection. That’s one reason many garages recommend combining your MOT with a full service rather than treating them as interchangeable.
A standard Class 4 MOT typically takes 45 to 60 minutes at the test centre, though total appointment time, including check-in and handover, often runs closer to an hour. Vehicles with more complex emissions systems or additional checks can take longer. For a full breakdown by vehicle type, see how long an MOT realistically takes.
The DVSA sets a legal maximum fee that no garage can exceed. For 2026, the caps are:
| Vehicle Class | Maximum Fee |
|---|---|
| Class 4 (cars, motor caravans, light vans up to 3,000kg) | £54.85 |
| Class 1 and 2 (motorcycles) | £29.65 |
| Class 7 (large vans, 3,000-3,500kg) | £58.60 |
This maximum has been frozen since April 2010. Garages are free to charge less, and most independent garages price well below the cap. The fee covers the test only; any repairs needed to pass are charged separately.
The DVSA publishes anonymised results from every MOT carried out in Great Britain, and the numbers are worth knowing before you book. Across all Class 4 cars, the initial failure rate typically sits around 27%, meaning roughly one in four cars fails on the first attempt. Pass rates vary significantly by make and model: some manufacturers post first-time pass rates in the low-to-mid 80% range, while others sit closer to 50%, largely reflecting the age and condition of the vehicles on the road rather than any single design flaw.
Failure rates also climb sharply with vehicle age. A three-year-old car is far more likely to sail through than a twelve-year-old one, simply because tyres, brakes, suspension bushes, and lighting components wear out over time regardless of how well a car has been looked after.
Across UK-wide DVSA data, the same categories dominate the fail list year after year:
Most of these are cheap to fix and easy to check yourself before you book. Our pre-test checklist walks through the 15 things worth checking at home, and if you want the full picture on why cars fail and how to avoid it, see the most common MOT failures in the UK.
Every MOT result now falls into one of several categories under the DVSA’s defect classification system:
A full explanation of what each category means for you, and which ones you genuinely need to worry about, is covered in the five MOT result categories explained.
If your car does fail, you’ll usually be offered a partial retest if the repair is carried out by the same garage within ten working days, often at no extra cost. The full detail on retest rules and fees is in our guide to MOT retest costs.
Only DVSA-approved test centres with a valid MOT testing station licence can carry out an MOT, and only qualified, certified testers can sign off the result. Every approved centre displays the blue “MOT Testing Station” sign, and results are recorded directly on the DVSA’s national database within minutes of the test finishing. For more on how testing stations are licensed and audited, see Understanding DVSA-approved MOT centres.
If your car passes, you’ll receive a VT20 pass certificate. If it fails, you’ll receive a VT30 refusal certificate, which lists every fault found. Both are increasingly issued digitally and recorded on the DVSA database, so a physical copy is useful but not the only proof your car has a valid MOT. More detail on what these certificates mean and what to do if you lose one is in our guide to the VT20 and VT30.
Gleam Tech Auto Ltd is a fully qualified and DVSA-approved Class 4 MOT testing station in Worthing, West Sussex, covering cars, motor caravans, and light vans up to 3,000kg. Our testers work through the full DVSA checklist with clear, honest reporting at every stage, and we never carry out repair work without your approval first.
Book your MOT test online or call us on 01903 206874 to check availability.