1,183 tests in 2025
MG Zt reliability and MOT pass rate
69.6% passed first time. The 30.4% fail rate is 7.8 points worse than the all-car average, on a median example 21 years old with 95,162 miles.
Pass rate
69.6%
22.6% of all cars failed; 30.4% of these did.
Fixed on the day
4.1%
Passed after a defect was put right during the visit.
Median at test
95,162 mi
21 years old.
Fail rate by age
| Age at test | Tests | Fail rate |
|---|---|---|
| 3-5 years | 1 | — |
| 6-9 years | 0 | — |
| 10-13 years | 0 | — |
| 14+ years | 1,182 | 30.5% |
What the Zt fails on
Share of failed tests with at least one fail item in each DVSA inspection section. A test can fail in several sections at once.
- Suspension10 dangerous51.4%
- Brakes50 dangerous43.1%
- Lamps, reflectors and electrical equipment2 dangerous32.5%
- Body, chassis, structure11 dangerous23.1%
- Seat belts and supplementary restraint systems16.9%
- Tyres59 dangerous16.1%
- Noise, emissions and leaks13.6%
- Visibility12.5%
Is the Zt getting worse?
The fail rate fell 3.9 points to 30.4% from 2022 to 2025 while the median one tested aged 3 years. Ageing alone would predict about 0.2 points, so it is holding up better than the fleet average for its age.
| Year | Tests | Median age | Fail rate | All cars | |
|---|---|---|---|---|---|
| 2022 | 1,918 | 18 | 34.3% | 22.5% | |
| 2023 | 1,690 | 19 | 32.2% | 22.8% | |
| 2024 | 1,278 | 20 | 29.3% | 23.2% | |
| 2025 | 1,179 | 21 | 30.4% | 22.6% |
Fail rate is first attempts at class 4 tests. Median age is the age of a typical Zt at its test that year, and it is the number to watch: across the whole fleet each extra year of age adds roughly 1.9 points to the fail rate, so a model whose age and fail rate rise together is simply getting older.
The exact defects that fail it
Every failure item DVSA recorded against a Zt in 2025, counted by how many tests each one appeared on.
- 1Rbt (sp): efficiency below requirements55 tests
- 2Component mounting prescribed areas: prescribed area excessively corroded significantly reducing structural strength51 tests
- 3SRS malfunction indicator lamp: warning lamp indicates a fault51 tests
- 4Rigid brake pipes: excessively corroded32 tests
- 5Ball joint: ball joint excessively worn30 tests
- 6Coil spring: fractured or broken26 tests
- 7Linkage ball joints: ball joint excessively worn26 tests
- 8Headlamp aim: projected beam image is obviously incorrect26 tests
What wears out first
Advisories are the tester flagging wear that is still legal. A typical Zt collects 3.5 of them per test, and these are the ones that come up most. Treat it as the running-repairs list for the next year or two.
- 1Rigid brake pipes: excessively corroded186 tests
- 2Brake discs: in such a condition that it is seriously weakened158 tests
- 3Tread depth: tread depth below requirements of 1.6mm130 tests
- 4Suspension arm: corroded and seriously weakened115 tests
- 5Sub-frame: corroded and seriously weakened108 tests
- 6Condition: has a tear, caused by separation or partial failure of its structure83 tests
- 7Coil spring: corroded so that its cross sectional area is reduced and seriously weakened74 tests
- 8Engine oil leaks: leaking excessively from engine56 tests
Questions
What is the MG Zt MOT pass rate?
69.6% of the 1,183 MG Zt first-attempt MOTs in 2025 passed. The fail rate of 30.4% compares with 22.6% across all cars. A further 4.1% passed after a defect was fixed during the test visit.
What does a MG Zt usually fail on?
The single most common failure is "Rbt (sp): efficiency below requirements", recorded on 55 failed tests, followed by "Component mounting prescribed areas: prescribed area excessively corroded significantly reducing structural strength" and "SRS malfunction indicator lamp: warning lamp indicates a fault". By section, suspension appears in 51.4% of failures, brakes appears in 43.1% of failures, lamps, reflectors and electrical equipment appears in 32.5% of failures.
Does age change the odds?
Sharply. At 3 to 5 years old the fail rate was 0%; at 14+ years it was 30.5%. The median MG Zt tested in 2025 was 21 years old with 95,162 miles.
Is the MG Zt getting less reliable?
The fail rate fell 3.9 points to 30.4% from 2022 to 2025 while the median one tested aged 3 years. Ageing alone would predict about 0.2 points, so it is holding up better than the fleet average for its age.
First-attempt class 4 tests, 2025, from DVSA’s anonymised MOT data (OGL v3, retrieved 2026-09-12). DVSA records newer cars trim by trim; this page adds every Zt trim together. Year-on-year figures come from the same DVSA extracts for 2026 and earlier years. Full method on the pass rates hub.
Other MG models
Checking a particular Zt?
The odds above are the model. The car in front of you has its own record: every test, every advisory, the mileage at each one.
Due a test? Find an approved MOT station near you.