MG
5,205 MOT tests analysed. lands in the middle of the pack — here's where GSs pass, fail, and end up on the retest sheet.
That's 1.1 points above the UK fleet average across our 1,984 tracked models — a confident result.
Pass
78.6%
Pass-after-fix
5.2%
Fail
15.8%
Avg miles
48,438
Pass + Pass-after-fix + Fail = 100%
Petrol cars first registered from January 2006 meet Euro 4 — compliant in London ULEZ, Birmingham CAZ, Bristol CAZ, and Glasgow LEZ.
Performance by cohort
2 year bands · 5,205 tests
Pass rate is broadly flat across the cohorts — new and old GS examples track each other at the test bay.
Pass
78.3%
Fail
15.6%
PRS
5.6%
Avg mileage at test
52,403 mi
Pass
79.1%
Fail
16.2%
PRS
4.3%
Avg mileage at test
40,907 mi
Cohort = vehicle's first-registration year band. Same model, different generations of build.
The picture
Across 3,258 MOT tests, the Gs returns 81.5% first-time pass — above the UK fleet average. The single most-logged Major fail is brake pads worn below 1.5 mm. Tyre tread under the limit and headlamp aim out of spec round out the top three. Average tested mileage sits at 41,134, which is the lens to read those failure rankings through. If you own one and the next test is close, the ranked list below is a sensible pre-test checklist.
ABI Insurance Group
Below the fleet average — generally reasonable to insure. Lower groups cost less to insure; UK fleet average is around Group 22.
Source: ABI Group Rating Panel · administered by Thatcham Research · groups cover standard variants; performance trims may sit higher. Browse all insurance groups →
12–28
out of 50
Filter failures:
Hide categories
Tick a category to hide it from rankings sitewide. Saved in this browser only.
Tyre tread depth not in accordance with the requirements
119 occurrences · 2.3% of tests
Warning device shows system malfunction
115 occurrences · 2.2% of tests
a brake lining or pad worn below 1.5mm
112 occurrences · 2.2% of tests
The aim of a headlamp is not within limits laid down in the requirements
105 occurrences · 2.0% of tests
ESC MIL indicates a system malfunction
83 occurrences · 1.6% of tests
Windscreen or window damaged or seriously discoloured but not adversely affecting driver's view
81 occurrences · 1.6% of tests
A rear registration plate lamp or light source missing or inoperative in the case of multiple lamps or light sources
78 occurrences · 1.5% of tests
A tyre pressure monitoring system malfunctioning or obviously inoperative
77 occurrences · 1.5% of tests
Wiper blade defective
58 occurrences · 1.1% of tests
An SRS malfunction indicator lamp (MIL) indicates a system malfunction
57 occurrences · 1.1% of tests
Counts cover Major and Dangerous defects logged at test. Advisory items excluded so this shows why a car was rejected, not just what the tester flagged in passing.
Worst-case fix budget · top 3 failures
£150–£335
If every one of this GS's most-logged Major fails hit at the same MOT, that's the real-world UK garage range. Reality is usually one or two items, not all of them. Open the estimator →
Try the calculator
Build your own retest budget.
Year-band analysis
First-time MOT pass rate split by registration band. Pass rates barely move across bands here, so the year you buy MG GS makes little measurable difference to MOT outcomes.
Best band to buy
79.1%
2018–2020 registration
the 2018–2020 band climbs to 79.1% — a 0.7-point improvement. Tests in this band average 40,907 miles — roughly 11K miles fewer on the clock than the older band. Failures here are mostly wear items: tread depth below requirements of 1.6mm, warning lamp indicates an ABS fault — the structural issues that drag down older examples don't appear in the top-10 for this band. The stricter post-2018 MOT test rules meant manufacturers had to tighten up emissions and electrical checks, but this band still shows far fewer major failures on suspension and bodywork than the older fleet.
Band to be cautious about
78.3%
Pre-2018 registration
On the older band (pre-2018), the data shows a 78.3% pass rate against a fleet average of 79.1% on the newer band. The main culprits logged at test: too low, less than 1.5 mm thick, and tread depth below requirements of 1.6mm. Average mileage on test for this band is 52,403 miles — high-mileage wear items are a recurring theme.
Best band to buy: 2018-2020 (79.1% first-time pass). Worst band to avoid: pre-2018 (78.3% pass). That's a 0.7-point spread across 3,409 older tests and 1,796 newer ones — year of build makes a material difference on this model.
Picked against this car's top failure patterns. Affiliate links to Amazon UK — we earn a small cut at no cost to you. Disclosed up-front, doesn't shape the data.
Item 01 · Amazon UK
Digital tyre-tread depth gauge
Five quid for a gauge beats £150 for a retest. UK MOT minimum is 1.6mm — most testers fail anything below 2mm to be safe.
Search Amazon UK
Item 02 · Amazon UK
Brake pad measurement gauge
Testers fail pads under 1.5mm. A wear gauge tells you if you've got two months left or two weeks.
Search Amazon UK
Item 03 · Amazon UK
Headlight restoration kit
Yellowed lenses fail the light-output test. A restoration kit lifts the haze in an afternoon for £20.
Search Amazon UK
My Motor World · affiliate
Affiliate links — small commission, no extra cost to you.
Summit
Summit ADRG-60 MG Replacement Stick-On Tinted Mirror Glass LHS
£7.69
View at My Motor World →
Autotek
Autotek Ford Nordic Blue 300ml
£14.29
View at My Motor World →
Motor World
Motor World MG Rover F 95-2002 Car Floor Mat Set
£32.99
View at My Motor World →
Motor World
Motor World Rover MGB Car Floor Mat Set
£32.99
View at My Motor World →
Click Mechanic · affiliate
Affiliate links — small commission, no extra cost to you.
Mobile mechanic · UK-wide
Book a mechanic at your door.
Fixed-price quotes upfront. No garage needed. Click Mechanic sends a vetted local mechanic to you — home, work, or roadside.
Use the failure ranking as a pre-test checklist or a haggling lever. Treat the headline pass rate as a fleet-wide trend, not a guarantee on any individual car.
If you own a GS and your last MOT looked nothing like the ranked failures above, that's normal — individual cars vary widely. The ranking shows the patterns testers flag most often across the country.
