MG 3 Mk1 (2019-2024) reliability
MG 3 Mk1 built around 2020: fails its MOT more often than average
MG 3 Mk1 models built around 2020 fail their MOT more often than similar cars the same age. Look closely at the tyres on any car you view.
Looking at an MG 3 Mk1?
Enter its number plate to see its full MOT history, risk rating and running costs.
Key figure
19% of MOT tests on MG 3 Mk1 models built around 2020 ended in a fail (retests included), against 12% for similar cars the same age.
Most common issue
The most common MOT issue on MG 3 Mk1 models built around 2020 involves the tyres.
Based on 13,635 tests of 3 models registered 2019-2024.
About 1 in 6 petrol 3 cars registered in 2022 (15.6%) failed their first MOT.
Based on 3,709 first MOTs (DVSA MOT results, 2025).
About 1 in 30 3 Mk1 MOTs (3.1%) failed and still hadn't passed 3 days later. That's for cars built around 2020 (5 years old), all fuels combined.
Based on 3,681 tests (DVSA MOT results, 2025). A fail that passed a retest within 3 days, even the same day, isn't counted. Nor is a fail with no later MOT on record.
About 1 in 15 3 Mk1 MOTs (6.6%) found at least one dangerous defect. These are cars built around 2020 (5 years old).
Based on 3,681 tests (DVSA MOT results, 2025). Dangerous is the most serious grade an MOT gives: a direct risk to road safety.
Mk1 fail rate by age
Fail rate is the share of MOT tests that ended in a fail. Retests count as tests. How we count fail rates Build years are worked out from age, so they are approximate. Tests counted are 2025 MOTs. Highest fail rate at 6 years old.
How the 3 Mk1 compares
At each age below, see how the 3 Mk1 holds up against other cars the same age. The averages combine all fuel types.
Based on 19,643 tests across 5 MG models, built around 2020 (5 years old).
Fail rate is the share of MOT tests that ended in a fail. Retests count as tests. How we count fail rates Build years are worked out from age, so they are approximate. Tests counted are 2025 MOTs.
What to check before viewing
The model's most common MOT issues, turned into things you can ask about or look for.
Independent inspection
High priorityHave an independent specialist inspect the car before you commit.
Brake discs
High priorityAsk for the date and mileage of the last disc replacement; visually check for a deep wear lip and rust pitting on each disc.
Brake pads
High priorityAsk when the pads were last replaced and check the warning-light history.
Tyres
Worth checkingCheck tread depth across the full width on all four; uneven wear suggests alignment or suspension issues.
Vehicle-specific check
Worth checkingCheck the car’s number plate on MOT Wise to see its own MOT history and any recalls for its build years.
Headlight aim
If you have timePark facing a wall at night and check the beam pattern is even and at the right height.
Other hatchbacks to compare
Other hatchbacks, with each one's figures taken at the same age as the 3 Mk1.
- 1
Mazda 2
Same body type, tested at the same age
- Fail rate
- 9.6%
- Fail, no pass in 3 days
- 0.8%
- Dangerous
- 3%
- Still registered at 10 years
- 95.2%
Lower fail rate: 9.6%, against 18.6% for the MG 3 Mk1, both built around 2020.
5,812 MOT tests on cars built around 2020
- 2
Toyota Corolla
Same body type, tested at the same age
- Fail rate
- 9.8%
- Fail, no pass in 3 days
- 0.9%
- Dangerous
- 2.9%
Lower fail rate: 9.8%, against 18.6% for the MG 3 Mk1, both built around 2020.
7 critical recall campaigns matching this model/build period.
20,631 MOT tests on cars built around 2020
- 3
Mini
Same body type, tested at the same age
- Fail rate
- 10.7%
- Still registered at 10 years
- 95.6%
Lower fail rate: 10.7%, against 18.6% for the MG 3 Mk1, both built around 2020.
Some figures could not be compared for these two cars. So this comparison uses the fail rate, share still registered and recalls only.
44,857 MOT tests on cars built around 2020
- 4
Suzuki SX4
Same body type, tested at the same age
- Fail rate
- 10.6%
Lower fail rate: 10.6%, against 18.6% for the MG 3 Mk1, both built around 2020.
Some figures could not be compared for these two cars. So this comparison uses the fail rate and recalls only.
1,440 MOT tests on cars built around 2020
- Fail rate
- = the share of MOT tests that ended in a fail. Retests count as tests.
- Fail, no pass in 3 days
- = the share of MOT tests that failed and still hadn't passed 3 days later. A fail that passed a retest within 3 days, even the same day, isn't counted.
- Dangerous
- = the share of MOT tests where the tester marked a fault as dangerous. It is against the law to drive the car until it is fixed.
- Still registered at 10 years
- = the share of cars still registered (taxed or declared off the road) 10 years after they were first registered.
Recall context
DVSA's recall list has no recalls filed under the MG 3 name. For the exact car, check with the maker or GOV.UK's recall checker.
What has gone wrong on 3 Mk1 cars built around 2020
The share of petrol cars that have ever failed an MOT on each part of the car. Based on 182 cars.
Rust, which the MOT calls corrosion: 8% of these cars show rust-related issues at this age.
Check the sills, subframe and brake pipes before you decide.
How 3 Mk1 cars have aged
How 3 Mk1 cars have aged
How fail rates have changed as these cars got older. Each line follows cars first registered in about the same year across several years of MOT data. Not a prediction for any one car.
Some lines cover only a year or two, so read this as a rough guide.
How each part holds up as Mk1 cars age
How each part holds up as Mk1 cars age
The share of petrol cars built 2017-2020 that have ever failed an MOT on each part of the car. Rates usually rise with age, but can dip slightly as cars leave the road.
| Part of the car | 5 years | 6 years | 7 years | 8 years |
|---|---|---|---|---|
| Suspension | 4% | 7% | 12% | 19% |
| Brakes | 6% | 18% | 22% | 26% |
| Emissions | 1% | 1% | 3% | 2% |
| Tyres | 18% | 26% | 26% | 32% |
| Lighting | 8% | 9% | 14% | 16% |
| Bodywork | No figure | No figure | No figure | 2% |
| Corrosion | 0% | 2% | 8% | 14% |
Based on petrol cars in the 2017-2020 build-year band, from 142 to 277 cars at each age.
Mk1 variants compared
3 Mk1 variants built around 2020
The fail rate for each 3 Mk1 variant, grouped by fuel. Each row counts fails per MOT test, the same way as the main fail rate chart.
Petrol
- 318.9%3,093 tests
- 3 EXCLUSIVE NAV VTI-TECH16.4%585 tests
Most common issues on MG 3 models of this age
This list covers every MG 3 built around 2020, whichever generation it is. We don't have a defect list for the Mk1 on its own.
Most common advisories and fails
In order of the share of MOT tests that recorded each one
- 118.3%Advisory
Tyre worn close to the legal limit or worn on the edge
- 216.3%Advisory
Tyre slightly damaged, cracking or perishing
- 310.8%Advisory
Brake disc worn, pitted or scored, but not seriously weakened
- 49.4%Advisory
Brake pads wearing thin
- 53.4%Advisory
Tyre has a cut that does not reach the ply or cords
Based on 3,681 tests
Looking at an MG 3 Mk1?
Enter its number plate to see its full MOT history, risk rating and running costs.
Frequently asked questions
Built around 2020 (5 years old), the MG 3 Mk1 (2019-2024) fails MOTs noticeably more often than typical for this age. This is based on 3,681 5-year-old MOT tests from DVSA data. Each retest counts as a test.