Check any MG before you buy
Enter a registration number to check its full dealer service history. See every dealer visit, dates, mileage, and work done so you know whether the maintenance that prevents these problems was actually carried out.
£6.99 service history · £7.49 premium car check · Full refund if no records found
How reliable are MG cars?
Our database covers 14 MG models and 77 documented faults across the range. Of these, 17 are classified as dangerous and a further 43 as major. Dangerous faults are those that can compromise vehicle safety or lead to complete mechanical failure if left unaddressed.
According to DVSA MOT test data, MG models fail at an average rate of 25.1%, which is above the 22.7% average across all manufacturers in our database. Reliability varies considerably between models. The GS is the strongest performer at just 17.6%, while the MGF has the highest failure rate at 29%.
If you are considering a used MG, researching the specific model and generation you are looking at makes a real difference. The most common failure areas across the range are suspension and body & rust, though each model has its own particular weak points. This page gives you a complete breakdown by severity, the models affected, and what repairs typically cost at UK garages.
MG reliability summary
Where MG problems occur
Understanding which systems are most prone to failure helps you focus during a test drive or pre-purchase inspection. Here is how MG's 77 known issues break down by area.
Suspension problems dominate, accounting for 19 of the 77 faults we track (25%). Issues in this area include Suspension component damage or corrosion and Suspension pins and bushes excessively worn. The most affected models are the 3 (3), the 6 (2), the B (2).
Body & Rust is the next most common area, with 15 documented faults (19%). Common faults here include Structural corrosion compromising rigidity and Structural corrosion compromising vehicle rigidity. The most affected models are the Midget (2), the Midget 1500 (2), the ZR (2).
We also track 13 brakes faults across the range (17%). Problems to watch for include Parking brake efficiency below requirements and Brake pipe corrosion (MK1). The most affected models are the 6 (2), the Midget (2), the TF (2).
Engine rounds out the top problem areas with 12 known issues (16%). Notable issues include Excessive emissions levels and Excessive emissions failing MOT limits. The most affected models are the MGB (2), the Midget 1500 (2), the TF (2).
Known MG faults by severity
Every fault in our database is rated by severity based on its potential safety impact and typical repair cost. Below is a sample of issues at each level, with links to the affected model pages where you can read the full details.
Dangerous
- Fuel system leaking excessively or fire risk 3
- Brake pipe corrosion (MK1) 6
- Structural corrosion compromising rigidity B
- Structural corrosion compromising vehicle rigidity B GT
- Extensive body corrosion MGB
+ 11 more dangerous issues across MG models
Major
- Suspension component damage or corrosion 3
- Suspension component corrosion and wear (MK1) 6
- Excessive emissions levels B
- Excessive emissions failing MOT limits B GT
- Electronic Stability Control system malfunction GS
+ 37 more major issues across MG models
Minor
- Brake disc premature wear (MK1) 6
- Steering rack gaiter deterioration B
- Warning system malfunction GS
- Lucas electrical system failures MGB
- Hydragas Suspension MGF
+ 11 more minor issues across MG models
Top issues across the MG range
The most common and severe problems found across all MG models, ranked by severity and how many models are affected.
Check any MG before you buy
Enter a registration number to check its full dealer service history. See every dealer visit, dates, mileage, and work done so you know whether the maintenance that prevents these problems was actually carried out.
£6.99 service history · £7.49 premium car check · Full refund if no records found
Problems by MG model
We track faults across 14 MG models. Each model page includes every known issue, generation-specific details, UK repair costs, and MOT failure data. Select a model below to see its full breakdown.
What to check before buying a used MG
Every used MG deserves a thorough inspection, but knowing the common weak points for your target model gives you a serious advantage. Since suspension faults are the most common across the range, pay particular attention to this area during any viewing or test drive.
The 17 dangerous-rated faults deserve special attention. These include Fuel system leaking excessively or fire risk, Suspension pin or joint likely to detach, Brake pipe corrosion (MK1). Any of these can compromise safety or result in repair bills running well into the thousands.
A complete dealer service history is one of the strongest indicators of how well a MG has been looked after. Many of the faults on this page are preventable or can be caught early through regular servicing. If the seller cannot produce service records, treat that as a significant red flag.
Check the MOT history carefully too. With a 25.1% average failure rate across the MG range, some advisories and minor failures are normal over the life of any car. What matters is the pattern: recurring failures in the same area suggest an underlying problem, while a history of clean passes is encouraging.
MG repair costs: what to expect
Across all documented faults, the average MG repair costs between £337 and £905 at an independent garage. At the top end, the most expensive single repair can reach £8,000 or more. Main dealer rates are typically 30% to 50% higher across the board.
The single most expensive MG repair in our database is Structural corrosion compromising vehicle rigidity, costing £500–£8,000 at an independent specialist.
These figures are based on reported UK repair costs and serve as a guide. Actual prices will vary depending on your location, the garage, and the parts required. Getting quotes from two or three specialists before committing to any major work is always worthwhile.
Buying a used MG? Check it first
Get the full picture before you commit. Our car check covers outstanding finance, write-off status, stolen records, plate changes and mileage discrepancies. Or check the service history to see whether the maintenance that prevents these problems was actually done.
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MG reliability FAQs
Are MG cars reliable?
Across 9 models with MOT data, MG has an average MOT failure rate of 25.1%. The most reliable model is the GS at 17.6% failure rate, while the MGF has the highest at 29%. We track 77 known issues across 14 MG models.
What are the most common MG problems?
The most common MG problems include Structural corrosion compromising rigidity, Head Gasket Failure, and Sill corrosion. Across all MG models we track 77 known issues, with 17 rated as dangerous.
Which MG model is most reliable?
Based on MOT failure data, the MG GS is the most reliable model with a 17.6% failure rate from 5,341 tests. The least reliable is the MGF at 29%. However, individual car condition and service history matter more than model averages.
How much do MG repairs cost?
MG repair costs at independent garages average £337-£905 per issue. The most expensive repairs can reach £8,000 or more. Main dealer rates are typically 30-50% higher. Costs vary significantly by model and issue, so check the specific model page for detailed pricing.
Should I get a vehicle check before buying a MG?
Yes. MG models have 77 known issues between them, including 17 dangerous and 43 major problems. A service history check (£6.99) shows whether scheduled maintenance was done, and a premium car check (£7.49) covers finance, stolen, write-off status. Both are essential before buying any used MG.