MG 3 reliability, MPG and running costs
Figures updated
The MG 3 is a supermini. In 2024 MOT tests it scored 70 for reliability (100 is average), ranking 425 of 442, and 24.6% failed first time against a UK average of 28.5%. Its most common MOT failure is wipers (2.4% of tests).
Ranked 425 of 442 cars in the 2024 MOT Reliability League, and 27 of 31 superminis
In 2024, 20,229 MG 3s aged 3 to 20 had an MOT and 24.6% failed first time (UK average 28.5%). Taking age and mileage into account, the MG 3 is 43% more likely to fail than the average car of the same age and mileage. At the first MOT, at three years old, 16.9% failed (UK 12.7%).
First-time fail rate
24.6%
UK 28.5%
Fail rate at 3 years
16.9%
UK 12.7%
Average miles a year
6,200
Typical age at test: 6 years
MG 3 MOT failure rate by age
Most common MG 3 MOT faults
- Wipers: does not clear the windscreen effectively2.4% of tests
- Headlamp aim: too low2.3% of tests
- SRS malfunction indicator lamp: warning lamp indicates a fault2.0% of tests
- Tread depth: tread depth below requirements of 1.6mm1.9% of tests
- Condition: has ply or cords exposed1.8% of tests
- Condition: has a cut in excess of the requirements deep enough to reach the ply or cords1.6% of tests
What the MG 3 fails on
| Area | Tests failing | vs similar cars |
|---|---|---|
| Lights and electrics | 7.3% | ▲ 1.6× as often |
| Tyres | 7.2% | ▲ 1.4× as often |
| Brakes | 6.0% | ▲ 1.9× as often |
| Visibility | 4.5% | ▲ 1.4× as often |
| Suspension | 4.5% | ▲ 1.4× as often |
| Seat belts and airbags | 2.2% | ▲ 6.5× as often |
| Steering | 1.3% | ▲ 1.8× as often |
| Exhaust and emissions | 1.2% | About average |
| Body and structure | 0.9% | ▼ 11% less often |
| Wheels | 0.1% | ▼ 38% less often |
How much is road tax on a MG 3?
Any MG 3 first registered from April 2017 pays the standard rate of £200 a year after its first year (2026/27 rates).
Work out tax for a specific carBuying a used MG 3?
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Compare the MG 3 with other superminis
Reliability, economy, car tax and running costs side by side.
Other MG models
Frequently asked questions
›Is the MG 3 reliable?
Its MOT record is worse than average: the MG 3 is 43% more likely to fail than the average car of the same age and mileage, with a reliability score of 70 in our 2024 league (100 is average).
›What are common problems with the MG 3?
The most common MOT fault is “Wipers: does not clear the windscreen effectively”, found in 2.4% of tests. It fails on seat belts and airbags and brakes more often than similar cars.
›How much is road tax on a MG 3?
Any MG 3 first registered from April 2017 pays the standard rate of £200 a year after its first year (2026/27 rates).
›How many MG 3s fail their MOT?
24.6% of MG 3s aged 3 to 20 failed their MOT first time in 2024, and 16.9% failed at their first MOT.
Sources: DVSA anonymised MOT tests 2024, all versions of the MG 3 combined (Open Government Licence v3.0). How we calculate the league.