Model Reports 4 min read Updated 18 Oct 2026

BMW 1 Series 2020: reliability & common MOT faults

In 2025, 88 in every 100 first MOTs on a 2020 BMW 1 Series were passes. Most common reason for a fail: Tyre condition (front).

Summary

The 2020 BMW 1 Series follows the pattern of the model years either side.

At a glance

How 23,203 first tests went in 2025.

Passed first time
88 in every 100
Did not pass first time
12 in every 1002,813 failed first-attempt tests
The typical car
5 yearsabout 38,234 miles
First tests counted
23,203

What failed most often

  1. Tyre condition (front)23 in every 100 failed tests
  2. Tyre tread depth (front)12 in every 100 failed tests
  3. Brake pads (rear)7 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 2020 BMW 1 Series vehicles in 2025, not a prediction that any one car will have them. Faults are grouped by part of the car. They come from MOT defect codes, not manufacturer bulletins, recalls or a diagnosis of any one car.

Suspension

Two faults. The strongest is the coil spring (rear): 3.2 times as often as on similar cars.

Figures below are measured across the 2,812 of 2,813 failed first attempts that recorded an odometer reading in 2025. Mileage is needed to compare like with like.

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.

Coil spring (rear)

Failed on 130 first tests3.2 times as often as similar carsLikely evidence

What it means

A missing bump stop rubber is not a reason to fail a coil spring. When the vehicle is jacked and lowered, a spring that does not correctly locate as the suspension returns to its normal running position is rejected as insecurely attached. A missing spring is Major, and graded Dangerous where directional control is affected.

Coil spring (front)

Failed on 87 first tests3.0 times as often as similar carsLikely evidence

What it means

A missing bump stop rubber is not a reason to fail a coil spring. When the vehicle is jacked and lowered, a spring that does not correctly locate as the suspension returns to its normal running position is rejected as insecurely attached. A missing spring is Major, and graded Dangerous where directional control is affected.

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
88in every 100
Passed on the first test.
Fixed at the station
1in every 100
Failed, then fixed at the test station the same day.
Failed
11in every 100
Did not pass, and were not fixed at the test station.

First-attempt pass 87.9% of 23,203 first tests (2025): only cars that passed first time count. Official-style pass 89.2%: cars fixed at the test station also count as a pass. The 1 fixed and the 11 not fixed make the 12 in every 100 that did not pass first time.

Petrol and diesel

First testsTypical mileagePassed first time, as testedPassed first time, same mileage
Petrol18,48236,328 miles8888
Diesel4,72047,108 miles8687

Figures are in every 100 first tests. Cars with more miles usually fail more often, so the same-mileage figure gives every fuel the mileage mix of all the cars in this year.

Same model, other years

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

4060801002005201020152020Older carsNewer cars
40608010020102020Older cars

Newer cars are younger, so look for a jump rather than the climb. A year earlier (2024), when these cars were a year younger, 89 in every 100 passed first time.

YearPassed first timeFirst tests
200461 in every 1001,046
200561 in every 1004,265
200662 in every 1006,355
200764 in every 1007,653
200865 in every 10012,308
200965 in every 10016,332
201066 in every 10019,698
201167 in every 10019,761
201266 in every 10026,485
201370 in every 10033,958
201473 in every 10028,931
201578 in every 10030,142
201679 in every 10030,546
201782 in every 10031,626
201883 in every 10025,832
201985 in every 10026,813
2020 This car88 in every 10023,203
202190 in every 10017,952
202291 in every 10013,102

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 2020 BMW 1 Series.

Of 2020 BMW 1 Series vehicles with under 27,000 miles, 91 in every 100 passed their 2025 MOT first time. With 53,000 miles or more, 85 in every 100 did.

Under 27,0004,833 tests
91
27,000–34,0004,132 tests
89
34,000–42,000 Typical car4,864 tests
87
42,000–53,0004,715 tests
87
53,000 and over4,652 tests
85

Petrol or diesel?

Typical mileagePassed first time,
as tested		Passed first time,
same mileage
Petrol36,328 miles8888
Diesel47,108 miles8687

Figures are in every 100 first tests. Petrol cars look better on the raw figures only because diesel cars have done more miles (typically 47,108 against 36,328). At the same mileage there is no clear difference between the two.

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 27,00034,000–42,00053,000 and over
Tyre condition (front)2.82.82.8
Tyre tread depth (front)0.61.42.2
Brake pads (rear)0.41.11.2
Coil spring (rear)0.40.70.6
Windscreen washers0.40.50.5

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

When a car fails

69in every 100

of failed cars had one item to fix.

9in every 100

of failed cars had three or more items to fix.

5in 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 2020 BMW 1 Series follows the pattern of the model years either side. Its main cause of failure was Tyre condition (front), about 23 in every 100 failed tests. In 2025, 87.9% of 23,203 first MOTs on the 2020 BMW 1 Series passed first time (PRS: items fixed at the station the same day, counted as a fail). The official-style rate including PRS is 89.2%. Among 2,813 failed first-attempt MOT tests (test year 2025), Coil spring (rear) appears more often than on similar cars (4.6% of those tests; 130 observed failures; about 3.2× 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 2020 BMW 1 Series at the first attempt were Tyre condition (front) (22.5%), Tyre tread depth (front) (11.8%) and Brake pads (rear) (6.8%), 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: Coil spring (rear) (4.6% of those tests; 130 observed failures; about 3.2× more often than similar cars). These are statistical signals, not a diagnosis of any individual car.
Coil spring (rear) shows up more often than on similar cars (4.6% of those tests; 130 observed failures; about 3.2× 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 2020 BMW 1 Series include Coil spring (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 2020 BMW 1 Series (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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