Model Reports 4 min read Updated 18 Oct 2026

Audi A1 2021: reliability & common MOT faults

In 2025, 89 in every 100 first MOTs on a 2021 Audi A1 were passes. Most common reason for a fail: Tyre condition (front).

Summary

The 2021 Audi A1 follows the pattern of the model years either side.

At a glance

How 13,504 first tests went in 2025.

Passed first time
89 in every 100
Did not pass first time
11 in every 1001,422 failed first-attempt tests
The typical car
4 yearsabout 28,359 miles
First tests counted
13,504

What failed most often

  1. Tyre condition (front)17 in every 100 failed tests
  2. Brake pads (front)12 in every 100 failed tests
  3. Tyre tread depth (front)12 in every 100 failed tests

How we count this. Data: UK MOT open data, 2025. Only Class 4 cars on their first MOT of the year are counted. A car that fails and is fixed at the test station still counts as a fail in the first-attempt rate. These are raw results, not adjusted for age, mileage, or peer mix. The MOT does not test engine or gearbox internals.

Note:

These are patterns across 2021 Audi A1 vehicles in 2025, not a prediction that any one car will have them. Faults are grouped by part of the car. A wear pattern follows age and use more than the way the car was built. They come from MOT defect codes, not manufacturer bulletins, recalls or a diagnosis of any one car.

Seat belts and restraints

One fault: seat belt condition (rear), 6.0 times as often as on similar cars.

Figures below are measured across the 1,422 failed first attempts in 2025 that had a mileage recorded, which allows a like-for-like comparison.

We only list faults with at least 20 failures and a rate of about 2.0 times that of similar cars, which keeps one-off results out of the list.

Seat belt condition (rear)

Failed on 104 first tests6.0 times as often as similar carsStrong evidence

What it means

Any sign of overstretching is a deficiency, and so is a cut anywhere on a child seat belt. On other belts the size of a cut decides it, with a stricter limit at the webbing edge than away from it. Webbing significantly stretched or weakened has rows in both Major and Dangerous grades.

Data: UK MOT open data, 2025. Compared with cars of the same age and mileage.

Brakes

One fault and three wear patterns. The strongest is the brake discs (rear): 2.7 times as often as on similar cars.

Brake discs (rear)

Failed on 55 first tests2.7 times as often as similar carsWear pattern

What it means

A brake disc or drum must be significantly worn before it is rejected, and being worn below the manufacturer's recommended limits is not a reason in itself. Significantly and obviously worn is Major, as is contamination with oil or grease. A disc or drum that is fractured, insecure, seriously weakened or missing is graded Dangerous.

Brake pads (front)

Failed on 169 first tests2.5 times as often as similar carsWear pattern

What it means

A pad worn down to its wear indicator, or contaminated with oil or grease, is Major. A pad worn below the set thickness limit, missing or incorrectly mounted is Dangerous. The manual treats an illuminated brake wear indicator as no reason for failure, although DVSA also lists an illuminated indicator as a Major row.

Also noted as an advisory

Testers also noted it as an advisory, worn but not yet failing, on 192 first tests, 2.1 times as often as on similar cars.

Brake performance (roller test, rear)

Failed on 33 first tests2.4 times as often as similar carsPossible evidence

What it means

A wheel with no recorded braking effort on the roller test is graded Dangerous. Inadequate effort, a brake grabbing severely, abnormal lag and excessive fluctuation in effort are each Major. So is significant brake effort recorded with no brake applied, which indicates a binding brake.

Brake discs (front)

Failed on 32 first tests2.1 times as often as similar carsWear pattern

What it means

A brake disc or drum must be significantly worn before it is rejected, and being worn below the manufacturer's recommended limits is not a reason in itself. Significantly and obviously worn is Major, as is contamination with oil or grease. A disc or drum that is fractured, insecure, seriously weakened or missing is graded Dangerous.

Data: UK MOT open data, 2025. Compared with cars of the same age and mileage. Advisories count notes recorded on failed first tests only.

Tyres

One wear pattern: tyre tread depth (rear), 2.3 times as often as on similar cars.

Tyre tread depth (rear)

Failed on 91 first tests2.3 times as often as similar carsWear pattern

What it means

Only primary grooves count when tread depth is assessed: those holding the wear indicators, or cut as deep as those when new. Shallower secondary grooves are ignored. Tread depth below the minimum for the vehicle is Dangerous, and so is a pattern not visible over the whole tread, but that second row applies only to vehicles that need the lower minimum.

Data: UK MOT open data, 2025. Compared with cars of the same age and mileage.

MOT pass rates

How first tests ended, and how the pass rates are counted.

Passed first time
89in every 100
Passed on the first test.
Fixed at the station
2in every 100
Failed, then fixed at the test station the same day.
Failed
9in every 100
Did not pass, and were not fixed at the test station.

First-attempt pass 89.5% of 13,504 first tests (2025): only cars that passed first time count. Official-style pass 91.3%: cars fixed at the test station also count as a pass. The 2 fixed and the 9 not fixed make the 11 in every 100 that did not pass first time.

Same model, other years

Passed first time in every 100, all tested in 2025.

406080100201020152021Older cars
40608010020102021Older cars

Newer cars are younger, so look for a jump rather than the climb.

YearPassed first timeFirst tests
201065 in every 1001,274
201164 in every 10015,034
201266 in every 10017,495
201367 in every 10021,298
201471 in every 10022,045
201574 in every 10022,636
201674 in every 10024,427
201777 in every 10021,991
201880 in every 10019,030
201984 in every 10019,545
202087 in every 10012,814
2021 This car89 in every 10013,504
202290 in every 10014,214

If you are buying one

What this year's MOT record means for the decision in front of you.

Mileage makes a modest difference on a 2021 Audi A1.

Of 2021 Audi A1 vehicles with under 19,000 miles, 93 in every 100 passed their 2025 MOT first time. With 40,000 miles or more, 86 in every 100 did.

Under 19,0002,825 tests
93
19,000–25,0002,474 tests
92
25,000–32,000 Typical car2,920 tests
89
32,000–40,0002,515 tests
87
40,000 and over2,770 tests
86

What to check at your mileage

How often each fault turned up on a failed first test, by the car's mileage. Read it as: what is likely to need looking at on a car like the one in front of you.

Under 19,00025,000–32,00040,000 and over
Tyre condition (front)1.91.71.8
Brake pads (front)0.01.22.2
Tyre tread depth (front)0.31.41.5
Windscreen washers0.30.81.2
Seat belt condition (rear)0.40.90.9

Faults per 100 first tests, by the car's mileage at the test.

When a car fails

63in every 100

of failed cars had one item to fix.

12in every 100

of failed cars had three or more items to fix.

4in every 100

of all first tests had a defect the tester marked dangerous (unsafe to drive away).

Every figure here is a first-attempt MOT rate from DVSA open data for this model line, for cars of this model year tested in 2025. Each mileage band holds a fifth of the tests. MOTs do not test engine or gearbox internals, so this is a pre-purchase checklist, not a full reliability score.

FAQs

Short answers about how to read this model-year guide.

The 2021 Audi A1 follows the pattern of the model years either side. Its main cause of failure was Tyre condition (front), about 17 in every 100 failed tests. In 2025, 89.5% of 13,504 first MOTs on the 2021 Audi A1 passed first time (PRS: items fixed at the station the same day, counted as a fail). The official-style rate including PRS is 91.3%. Among 1,422 failed first-attempt MOT tests (test year 2025), Seat belt condition (rear) appears more often than on similar cars (7.3% of those tests; 104 observed failures; about 6.0× more often than similar cars). There is no single reliability score here; this is a pre-purchase checklist built from DVSA open data, not a guarantee for any individual car.
Ranked by how often they were actually recorded, the items that most often failed a 2021 Audi A1 at the first attempt were Tyre condition (front) (17.4%), Brake pads (front) (11.9%) and Tyre tread depth (front) (11.6%), each as a share of the year's failed first attempts. That is what goes wrong most often on the car. The common faults table shows a different measure: faults that are unusual compared with similar cars.
Among failed first-attempt tests we highlight patterns that appear more often than on similar cars. Top example: Seat belt condition (rear) (7.3% of those tests; 104 observed failures; about 6.0× more often than similar cars). These are statistical signals, not a diagnosis of any individual car.
Seat belt condition (rear) shows up more often than on similar cars (7.3% of those tests; 104 observed failures; about 6.0× more often than similar cars). That does not prove a design fault. Age, mileage, and how the car was used still matter. Treat it as a pre-purchase checkpoint, not a manufacturer service bulletin.
Common MOT problem areas for the 2021 Audi A1 include Seat belt condition (rear), Brake performance (roller test, rear). These are the faults that stand out compared with similar cars, not a complete list of what can go wrong on any individual car.
This page highlights MOT failure patterns for the 2021 Audi A1 (registration year) using UK DVSA open data for the selected test year. Patterns are compared with cars of a similar age and mileage. It is a buyer checklist from MOT defect statistics, not a full service history or manufacturer service-bulletin list.
No. MOT tests do not cover engine internals, gearboxes, or many electronic modules. Patterns here come from MOT defect statistics only and should not be read as engine or gearbox reliability scores.

About this data

How this page is built and what it can (and can't) say.

These figures come from UK MOT open data for this model year. We surface common failure patterns against similar cars, not a full reliability score, and not a pass/fail verdict on any individual vehicle.

2024 2025

What we include

UK Class 4 cars only. Normal MOT tests (not retests); first test per vehicle per calendar year; results pass, PRS, or fail.

Same-day repairs

PRS means the car failed items that were fixed at the test station and then passed the same day. We count PRS as a first-attempt fail in headline rates so same-day repairs do not hide problems.

How we compare

We compare this model year with other Class 4 cars of similar age and mileage in the same test year. This model family is left out of the peer group so the car is not measured against itself.

What this does not cover

  • MOTs do not cover engine internals, gearboxes, or many electronics; this is not a full reliability score.
  • Common faults come from MOT defect stats, not manufacturer TSBs or recalls.
  • Age and mileage matching reduces, but does not remove, differences in how cars were used and maintained.
  • If the data for a car is too thin to say anything useful, we say so rather than guess.

Contains public sector information licensed under the Open Government Licence v3.0.

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