Peugeot 308 2021: reliability & common MOT faults

At a glance

How 1,538 first tests went in 2025.

Passed first time: 83 in every 100
Did not pass first time: 17 in every 100254 failed first-attempt tests
The typical car: 4 yearsabout 35,776 miles
First tests counted: 1,538

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 Peugeot 308 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.

Lamps and electrical

One fault: headlight (front), 6.6 times as often as on similar cars.

Figures below are measured across the 254 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.

Headlight (front)

Failed on 37 first tests6.6 times as often as similar carsLikely evidence

What it means

On vehicles first used on or after a set date, a halogen headlamp unit converted to take HID or LED bulbs fails for light source and lamp not compatible, which is Major. A complete unit built with those light sources is not failed for that. The precise position of the lamps is not part of the inspection beyond a visual look to see that they sit at about the same height and distance from each side.

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: 83in every 100; Passed on the first test.
Fixed at the station: 6in 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 83.5% of 1,538 first tests (2025): only cars that passed first time count. Official-style pass 88.7%: cars fixed at the test station also count as a pass. The 6 fixed and the 11 not fixed make the 17 in every 100 that did not pass first time.

Petrol and diesel

First testsPassed first time, as tested

Petrol79787

Diesel73580

Figures are in every 100 first tests.

Same model, other years

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

Newer cars are younger, so look for a jump rather than the climb. A year earlier (2024), when these cars were a year younger, 88 in every 100 passed first time.

Year	Passed first time	First tests
2007	45 in every 100	556
2008	49 in every 100	5,515
2009	49 in every 100	8,392
2010	52 in every 100	9,728
2011	57 in every 100	8,047
2012	55 in every 100	8,838
2013	54 in every 100	9,434
2014	62 in every 100	11,161
2015	67 in every 100	12,989
2016	69 in every 100	13,556
2017	72 in every 100	8,588
2018	77 in every 100	8,002
2019	81 in every 100	6,840
2020	85 in every 100	3,618
2021 This car	83 in every 100	1,538
2022	88 in every 100	3,689

FAQs

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

Is the 2021 Peugeot 308 reliable?

A 2021 Peugeot 308 passed first time about 3 in every 100 less often than the average of the 2020 and 2022 model years. In 2025, 83.5% of 1,538 first MOTs on the 2021 Peugeot 308 passed first time (PRS: items fixed at the station the same day, counted as a fail). The official-style rate including PRS is 88.7%. Among 254 failed first-attempt MOT tests (test year 2025), Headlight (front) appears more often than on similar cars (14.6% of those tests; 37 observed failures; about 6.6× 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.

What common MOT faults stand out on the Peugeot 308 2021?

Among failed first-attempt tests we highlight patterns that appear more often than on similar cars. Top example: Headlight (front) (14.6% of those tests; 37 observed failures; about 6.6× more often than similar cars). These are statistical signals, not a diagnosis of any individual car.

Why does Headlight (front) stand out?

Headlight (front) shows up more often than on similar cars (14.6% of those tests; 37 observed failures; about 6.6× 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.

What are common problems with the 2021 Peugeot 308?

Common MOT problem areas for the 2021 Peugeot 308 include Headlight (front). These are the faults that stand out compared with similar cars, not a complete list of what can go wrong on any individual car.

What does this Peugeot 308 2021 MOT report cover?

This page highlights MOT failure patterns for the 2021 Peugeot 308 (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.

Does this include engine and gearbox problems?

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.