75.9%
Audi A3
Audi A3 vs Mercedes-Benz A-Class
Buying a used Audi A3 or Mercedes-Benz A-Class? Compare their MOT pass rates, common problems, mileage and how they hold up as they get older.
Already found one of them? Check its finance, write-off, theft, mileage and keeper history with a £15 vehicle history report.
MOT pass rate head to head
Initial MOT tests in 2025, retests excluded. The UK average across all cars is 72.3%.
78.4%
Mercedes-Benz A-Class
2.5
percentage point gap in the Mercedes-Benz A-Class's favour
A real gap, but not a decisive one on its own. The figures come from 420,947 tests of the Audi A3 and 366,292 of the Mercedes-Benz A-Class. The Audi A3 also arrives at test with roughly 25,515 more miles on average, which usually says more about who buys it and what they use it for than about how long it lasts.
A pass rate is not a reliability score. It records whether cars met the roadworthiness standard on test day.
Which one holds up better with age?
A headline pass rate mixes three-year-old cars with fifteen-year-old ones. Split by age, you can see what each model does over time.
| Age at test | A3 | A-Class |
|---|---|---|
| 3 to 5 years | 88.2% | 87.9% |
| 6 to 10 years | 82.8% | 77.7% |
| 11 years and over | 64.7% | 63.6% |
Both models age at much the same rate, losing around 23.9 percentage points between the youngest and oldest groups. Neither has an advantage worth paying for on this measure.
What each one fails on
The areas testers recorded most often across every failed 2025 test for each model, as a share of recorded failure items.
Audi A3
Mercedes-Benz A-Class
The Audi A3 fails most often on suspension, the Mercedes-Benz A-Class on tyres. Two different things to check on a viewing, and two different conversations to have with the seller. These are recorded failure categories, not faults every car has.
The specific items testers wrote down
One level deeper than the category: the individual defects recorded most often on each model.
Audi A3
- Coil spring fractured or broken
- Tread depth tread depth below requirements of 1.6mm
- Linkage ball joint dust cover ball joint dust cover no longer prevents the ingress of dirt
Mercedes-Benz A-Class
- Tread depth tread depth below requirements of 1.6mm
- Coil spring fractured or broken
- Brake pads less than 1.5 mm thick
What this comparison can't tell you
Everything above describes two models across the whole UK fleet. It says nothing about the one car in the advert. Two A3s of the same year and mileage can be worth thousands apart because of finance, a write-off, a theft record or a clocked odometer, none of which appear in MOT data.
Check the car you are about to buy. One £15 report, instant results, backed by a £30,000 data guarantee.
- Outstanding finance
- Write-off records
- Stolen markers
- Mileage history
- Previous keepers
Read more on each car
Other comparisons with these cars
Audi A3 vs Mercedes-Benz A-Class FAQs
Is the Audi A3 or the Mercedes-Benz A-Class more likely to pass its MOT?
The Mercedes-Benz A-Class passed 78.4% of its initial MOT tests in the DVSA 2025 data against 75.9% for the Audi A3, a gap of 2.5 percentage points. That is a fleet-wide average, not a prediction about the specific car you are looking at.
Does a higher MOT pass rate mean a more reliable car?
No. An MOT records whether a vehicle met the roadworthiness standard on the day it was tested. It does not test the engine, clutch or gearbox, and it does not measure how often a car breaks down. Pass rates are useful for comparing how two models are holding up across the whole UK fleet, and nothing more than that.
Which is cheaper to keep on the road, the Audi A3 or the Mercedes-Benz A-Class?
This data does not price servicing or repairs, so it cannot answer that directly. What it does show is what each model most often fails on, which is a fair guide to where the money goes. The Audi A3 fails most often on suspension. The Mercedes-Benz A-Class fails most often on tyres.
Which one has covered more miles by MOT time?
The average Audi A3 arrived at its 2025 MOT on 88,070 miles, against 62,555 for the Mercedes-Benz A-Class. That usually reflects who buys each car and what they use it for rather than how long it will last.
How do I check the actual Mercedes-Benz A-Class I have found?
Enter its registration. A Carpeep car history check reports outstanding finance, insurance write-off markers, stolen markers, the mileage recorded at every MOT, previous keepers, tax and MOT status, import and export markers and scrapped status in one £15 report. None of that appears in model-level MOT statistics.
MOT figures are aggregated from the DVSA MOT Anonymised data set for 2025 (class 4 initial tests, retests excluded), licensed under the Open Government Licence v3.0. MOT results describe roadworthiness at test, not mechanical reliability.