Triumph Stag MOT pass rate and common failures
In 2025, 81.8% of Triumph Stag MOT tests were a first-time pass, across 1,243 tests in Great Britain. For all cars it was 71.5%.
Compared with cars of the same age
Older cars fail more often, so a model that’s mostly a few years old will look better than one that’s mostly 12. These figures compare like with like.
At 3–5 years
–
Too few tests at this age to say.
At 6–10 years
–
Too few tests at this age to say.
At 11 years and over
81.8%
All cars: 61.3% (20.5 points better). 1,242 tests.
Figures by age, with typical mileage
| Age (years) | Tests | First-time pass | All cars | Typical mileage |
|---|---|---|---|---|
| 20+ | 1,242 | 81.8% | 61.4% | 56,250 miles |
Typical mileage is the median reading at the test, to the nearest 2,500 miles.
What fails most often
The share of Triumph Stag MOT tests that failed on at least one item in each area, against all cars. A test can fail on several areas at once.
| Area | Stag | All cars |
|---|---|---|
| Lamps, reflectors and electrical equipment | 15.7% | 16.6% |
| Brakes | 9.0% | 10.2% |
| Suspension | 5.7% | 13.7% |
| Visibility | 5.3% | 5.2% |
| Noise, emissions and leaks | 3.5% | 4.0% |
| Steering | 3.5% | 2.5% |
| Body, chassis, structure | 1.9% | 4.2% |
| Seat belts and supplementary restraint systems | 0.9% | 1.1% |
Most common reasons for failing
- Non catalyst emissions: emissions carbon monoxide content excessive failed 2.3% of tests · what this means
- Service brake imbalance: across an axle failed 2.2% of tests · what this means
- Washers: not working failed 1.9% of tests · what this means
- Position lamp: not working failed 1.8% of tests · what this means
- Headlamp: not working on dipped beam failed 1.7% of tests · what this means
- Headlamp: not working on main beam failed 1.5% of tests · what this means
- Headlamp aim: too low failed 1.4% of tests · what this means
- Washers: provides insufficient washer liquid failed 1.4% of tests · what this means
- Steering rack: gaiter missing or no longer prevents the ingress of dirt failed 1.4% of tests · what this means
- Rbt (sp): efficiency below requirements failed 1.4% of tests
Checking a particular Stag?
See its own MOT history, mileage record and advisories in plain English. Free, no sign-up.
About these figures
- They cover every Stag version DVSA records under this name (engines, trims and generations together), on its first MOT test of each visit. A “pass with rectification” (fixed within an hour) counts as a fail, as in DVSA’s own statistics.
- Cars under three years old are left out, because the few tested that young are mostly taxis.
- Fuel mix of the cars tested: petrol 99.9%, electric 0.1%.
- A pass rate describes the model, not any one car. How a car has been looked after matters more.
Download these figures (CSV) · Other Triumph models · All makes
Source: DVSA anonymised MOT test data for 2025. Contains public sector information licensed under the Open Government Licence v3.0. Our own analysis; not produced or endorsed by DVSA.