1,408 tests in 2025
Smart Roadster reliability and MOT pass rate
75% passed first time. The 25% fail rate is 2.4 points worse than the all-car average, on a median example 21 years old with 77,450 miles.
Pass rate
75%
22.6% of all cars failed; 25% of these did.
Fixed on the day
5.3%
Passed after a defect was put right during the visit.
Median at test
77,450 mi
21 years old.
Fail rate by age
| Age at test | Tests | Fail rate |
|---|---|---|
| 3-5 years | 0 | — |
| 6-9 years | 0 | — |
| 10-13 years | 0 | — |
| 14+ years | 1,408 | 25% |
What the Roadster fails on
Share of failed tests with at least one fail item in each DVSA inspection section. A test can fail in several sections at once.
- Lamps, reflectors and electrical equipment4 dangerous54%
- Brakes23 dangerous35.5%
- Suspension6 dangerous29%
- Visibility12.5%
- Tyres36 dangerous10.8%
- Noise, emissions and leaks9.9%
- Body, chassis, structure3 dangerous9.7%
- Steering1 dangerous9.4%
The exact defects that fail it
Every failure item DVSA recorded against a Roadster in 2025, counted by how many tests each one appeared on.
- 1Horn: not working44 tests
- 2Position lamp: not working42 tests
- 3Rear fog lamp: not working37 tests
- 4Ball joint: ball joint excessively worn29 tests
- 5Rigid brake pipes: excessively corroded29 tests
- 6Headlamp: not working on dipped beam24 tests
- 7SRS malfunction indicator lamp: warning lamp indicates a fault23 tests
- 8Individual direction indicators: incorrect colour23 tests
What wears out first
Advisories are the tester flagging wear that is still legal. A typical Roadster collects 3.28 of them per test, and these are the ones that come up most. Treat it as the running-repairs list for the next year or two.
- 1Rigid brake pipes: excessively corroded248 tests
- 2Engine oil leaks: leaking excessively from engine148 tests
- 3Condition: has a tear, caused by separation or partial failure of its structure146 tests
- 4Brake discs: in such a condition that it is seriously weakened138 tests
- 5Coil spring: corroded so that its cross sectional area is reduced and seriously weakened112 tests
- 6Tread depth: tread depth below requirements of 1.6mm99 tests
- 7Ball joint: ball joint excessively worn74 tests
- 8Individual direction indicators: incorrect colour71 tests
Questions
What is the Smart Roadster MOT pass rate?
75% of the 1,408 Smart Roadster first-attempt MOTs in 2025 passed. The fail rate of 25% compares with 22.6% across all cars. A further 5.3% passed after a defect was fixed during the test visit.
What does a Smart Roadster usually fail on?
The single most common failure is "Horn: not working", recorded on 44 failed tests, followed by "Position lamp: not working" and "Rear fog lamp: not working". By section, lamps, reflectors and electrical equipment appears in 54% of failures, brakes appears in 35.5% of failures, suspension appears in 29% of failures.
Does age change the odds?
Sharply. At 3 to 5 years old the fail rate was n/a%; at 14+ years it was 25%. The median Smart Roadster tested in 2025 was 21 years old with 77,450 miles.
First-attempt class 4 tests, 2025, from DVSA’s anonymised MOT data (OGL v3, retrieved 2026-09-12). DVSA records newer cars trim by trim; this page adds every Roadster trim together. Year-on-year figures come from the same DVSA extracts for 2026 and earlier years. Full method on the pass rates hub.
Other Smart models
- Fortwo 25.6%
- Eq Fortwo 5.4%
- Eq Forfour 10.9%
Checking a particular Roadster?
The odds above are the model. The car in front of you has its own record: every test, every advisory, the mileage at each one.
Due a test? Find an approved MOT station near you.