72.7%
Smart Forfour
Smart Forfour MOT pass rate and common problems
The Smart Forfour passed 72.7% of its initial MOT tests in 2025, in line with the 72.3% UK average. The item testers recorded most often was tread depth below requirements of 1.6mm.
Checking a specific car? Its own results, advisories and recorded mileages are in a free MOT history check.
How the Forfour compares
Initial MOT tests in 2025, retests excluded. A car that failed and was repaired at the test station counts as a fail.
71.3%
Smart average
72.3%
UK average, all cars
The Forfour runs 1.4 points ahead of the Smart average. It is 1st of the 4 Smart models in the data. The average Forfour arrived at its test 9 years old with 47,781 miles recorded.
A pass rate records whether cars met the roadworthiness standard on test day. It is not a reliability score, and part of any gap reflects how old the tested cars were.
Forfour MOT pass rate by age
The same 2025 tests split by the car's age at test.
Smart Forfour cars aged 3 to 5 years passed 83.4% of MOT tests. For cars aged 11 years and over that fell to 56.3%, a drop of 27.1 percentage points.
| Age at test | Tests | Pass rate | vs UK average |
|---|---|---|---|
| 3 to 5 years | 2,487 | 83.4% | 11.1 pts above |
| 6 to 10 years | 20,106 | 72.7% | In line |
| 11 years and over | 2,052 | 56.3% | 16 pts below |
That is a steep decline with age, so the headline rate flatters older examples. The UK average of 72.3% covers cars of every age, so compare like with like.
Where Forfour failures cluster
Every failure item recorded on Smart Forfour cars in 2025, grouped into the DVSA's test areas.
Lamps, reflectors and electrical equipment and tyres together account for 40.2% of recorded failure items. These are recorded failures across the model, not faults every car has.
The 10 most common Forfour MOT failures
Specific items recorded on Smart Forfour cars that failed their 2025 MOT, as a share of all recorded failure items.
Together these 10 items make up 46.5% of everything testers recorded against failed Smart Forfour cars. The rest is spread across many smaller items, and one failed test often records several at once.
What to look at on a Forfour
The recorded failures above, grouped by area, biggest first.
1
Tyres
Recorded most often: tread depth below requirements of 1.6mm, condition has ply or cords exposed and condition has a cut in excess of the requirements deep enough to reach the ply or cords. 13.4% of failure items.
2
Visibility
Recorded most often: wipers does not clear the windscreen effectively and washers provides insufficient washer liquid. 9.9% of failure items.
3
Suspension
Recorded most often: ball joint excessively worn and coil spring fractured or broken. 9.7% of failure items.
4
Noise, emissions and leaks
Recorded most often: catalyst emissions lambda reading after 2nd fast idle outside specified limits and malfunction indicator lamp inoperative or indicates a malfunction. 7.9% of failure items.
The car's own MOT history matters more than any model average. A free MOT history check shows whether a specific Forfour has failed on these items before, or had them noted as advisories. Buying one? See the used Smart Forfour buying guide.
Already found one?
Check its finance, write-off, theft, mileage and keeper history with a £15 vehicle history report.
Smart Forfour MOT FAQs
What is the Smart Forfour MOT pass rate?
72.7% of Smart Forfour cars passed their initial MOT first time in 2025, from 25,039 tests. That is in line with the 72.3% average for all cars, and ranks 298th of 575 models.
What does a Smart Forfour most commonly fail its MOT on?
The item testers recorded most often on Smart Forfour cars failing their 2025 MOT was tread depth below requirements of 1.6mm, on 7.2% of failure items. Next were wipers does not clear the windscreen effectively (6.5%) and ball joint excessively worn (6.1%).
Which area causes the most Smart Forfour MOT failures?
Across every recorded failure item, the largest area was lamps, reflectors and electrical equipment at 21.5%, followed by tyres at 18.7%.
Do older Smart Forfour cars fail their MOT more often?
Smart Forfour cars aged 3 to 5 years passed 83.4% of MOT tests in 2025, against 56.3% for cars aged 11 years and over.
Does this mean every Smart Forfour has these problems?
No. These are the items testers recorded across every Smart Forfour that failed in 2025. They show where the model most often needs attention, not the condition of any individual car.
How do I see a specific Smart Forfour's MOT history?
Enter its registration on the free Carpeep MOT history check to see that car's own test results, failures, advisories and recorded mileages.
MOT figures are aggregated from the DVSA MOT Anonymised data set for 2025: class 4 initial tests, retests excluded, with failure items from failed tests (advisories and minor defects excluded), licensed under the Open Government Licence v3.0. MOT results describe roadworthiness at test, not mechanical reliability.