14.8%
Fluid leak
The vehicle is leaking a fluid — oil, coolant, fuel or hydraulic. A slight seep is common on older cars; a continuous drip is both a road hazard and a sign of something failing.
MOT wording: Oil leak, but not excessive
MGUsed-car reliability
How reliable is a used MG?
At 7 years old, the average MG fails its MOT more often than the average UK car.
MOT fail rate · 7-year-old cars
MG22.4%
UK average16.6%
Fails more often than the average 7-year-old car (about 1 in 6 MOTs, 16.6%)
Where to start
The lowest and highest fail rates in the MG range
The MG models whose MOT tests at 7 years old most and least often ended in a fail.
What actually goes wrong
What breaks on MG cars
The most common MOT faults across the MG range, in plain English. Models with more MOT tests count for more. The percentage is the share of MOT tests on MG cars that recorded that defect.
14.2%
Brake disc or drum
A brake disc or drum is excessively worn, scored, cracked, warped, or corroded. These are the rotating parts that the pads or shoes press against to slow the car.
MOT wording: Brake disc worn, pitted or scored, but not seriously weakened
13.0%
Tyre condition
A tyre is worn, cut, damaged or otherwise not fit for the road. Tyres are the only thing connecting the car to the road, so this is always worth taking seriously.
MOT wording: Tyre worn close to the legal limit or worn on the edge
11.7%
Suspension arms, struts and anti-roll bar
A suspension arm, wishbone, strut, sub-frame, or anti-roll bar is worn, cracked, bent, or has excessive play. These structural parts hold the wheels in position and control body lean in corners.
MOT wording: Suspension part corroded, but not seriously weakened
Across all MG models; models with more MOT tests count for more.
The whole range
Every MG that ranks, in plain English
For each model, one number: the share of its MOT tests at 7 years old that ended in a fail. Retests count as tests. Lower is better. The UK average (about 1 in 6 MOTs, 16.6%) is shown for reference. Only models with enough MOT data at 7 years old are ranked. The rest sit just below, unranked.
3 models
MG GS
The lowest 7-year fail rate of any MG here.
21.4%fail rate at 7 years old
MG ZS
Among the lower fail rates in the MG range at 7 years old.
21.9%fail rate at 7 years old
MG 3
Above the MG average, and at or above the UK average.
23.3%fail rate at 7 years old
Fail rates are the share of MOT tests on 7-year-old cars ending in a fail, retests included (DVSA MOT results, 2025). UK average across all makes at the same age: 16.6%. How we count fail rates
Not directly comparable with the figures at 7 years old
Shown unranked. These models don’t have enough MOT data at 7 years old yet. They’re either too new (few cars old enough) or too old (few still on the road). Each is shown at the age with the most tests, so the percentages aren’t directly comparable to the list above.
Too old to rank
MG RV8
9.5%fail rate at 25+ years old · 603 MOT tests
Too new to rankMG HS
10.7%fail rate at 3 years old · 18,457 MOT tests
Too new to rankMG 4
11.1%fail rate at 3 years old · 2,188 MOT tests
Too new to rank
MG 5
14.3%fail rate at 3 years old · 8,769 MOT tests
Too old to rankMG Midget
17.6%fail rate at 25+ years old · 1,109 MOT tests
Too old to rankMG TF
25.9%fail rate at 21 years old · 3,254 MOT tests
Too old to rankMG MGF
27.3%fail rate at 25+ years old · 4,027 MOT tests
Too old to rankMG ZR
27.7%fail rate at 21 years old · 653 MOT tests
Too old to rankMG ZT
27.8%fail rate at 21 years old · 800 MOT tests
Too old to rank
MG 6
29.5%fail rate at 10 years old · 454 MOT tests
Looking at one in particular?
Averages tell you the odds across the range. Enter a number plate to see that car’s own MOT history, its risk rating, and what’s likely to need attention.