Most Reliable Mercedes-Benz Models: Real MOT Data Analysis
We analysed 1,662,304 real UK MOT tests to reveal which Mercedes-Benz models pass most often, which years to buy, and which to avoid entirely.
1,662,304 MOT tests analysed
Real DVSA data covering every Mercedes-Benz model from 2000-2023
Key Findings
Most Reliable Model
Mercedes-Benz GT
92.2% pass rate
Best Single Year
SL 2005 Petrol
82.9% pass rate
Mercedes-Benz vs National Average
76.9% vs 71.5%
+5.4% above average
Proven Durability Champion
SL 2005
+25.6% at 13+ years
Mercedes-Benz has built its reputation on reliability, but does the data back it up? We analysed 1,662,304 real MOT tests from the DVSA database to find out exactly which Mercedes-Benz models live up to the hype and which ones fall short.
This isn't survey data or owner opinions. These are actual pass/fail results from UK garages, covering every Mercedes-Benz model sold in the UK from 2000 to 2023.
How Mercedes-Benz Compares to Rivals
Mercedes-Benz ranks #27 out of 75 manufacturers with a 76.9% average MOT pass rate. That's above the national average of 71.5%:
| Manufacturer | Pass Rate | Rank | Tests Analysed |
|---|---|---|---|
| Lexus | 83.3% | #18 | 157,583 |
| Bmw | 78.5% | #22 | 1,808,787 |
| Jaguar | 78.2% | #23 | 336,140 |
| Audi | 77.9% | #25 | 1,663,207 |
| Mercedes-Benz | 76.9% | #27 | 1,662,304 |
| Volvo | 73.2% | #35 | 556,785 |
The verdict: Lexus maintains a lead among competitors, while Mercedes-Benz sits at #27. However, newer Mercedes-Benz models significantly outperform this average.
Best Mercedes-Benz Models by MOT Pass Rate
Looking at overall reliability across all years, here's how Mercedes-Benz's core models rank against the 71.5% national average:
| Model | Pass Rate | vs National (71.5%) | Tests | Years |
|---|---|---|---|---|
| GT | 92.2% | +20.7% | 1,266 | 2015-2019 |
| G | 92.0% | +20.5% | 862 | 2019-2020 |
| B | 90.4% | +18.9% | 6,442 | 2019-2020 |
| GLB 220 AMG LINE PREM D 4M A | 89.8% | +18.3% | 1,607 | 2020-2021 |
| GLC | 88.3% | +16.8% | 71,902 | 2015-2021 |
| GLE | 88.3% | +16.8% | 26,142 | 2015-2021 |
| GLS | 88.1% | +16.6% | 2,090 | 2016-2020 |
| EQC 400 AMG LINE 4MATIC | 87.6% | +16.1% | 1,495 | 2020-2020 |
| A | 87.6% | +16.1% | 82,826 | 2013-2021 |
| SLC | 87.5% | +16.0% | 8,707 | 2016-2020 |
Top performer
The GT dramatically outperforms other Mercedes-Benzs with an 92.2% pass rate, putting it among the most reliable cars in the database.
Proven Durability Champions: Which Mercedes-Benz Models Age Best?
These Mercedes-Benz models have proven their durability with 11+ years of real-world MOT data. They're compared against the national average for cars of the same age:
High-confidence data: Only vehicles with 11+ years of MOT history and 500+ tests are included in this ranking.
| Model | Year | Fuel | vs Same-Age Average | Tested At | Pass Rate |
|---|---|---|---|---|---|
| SL | 2005 | Petrol | +25.6% | 13+ years | 82.9% |
| SL | 2008 | Petrol | +25.5% | 13+ years | 82.8% |
| SL | 2004 | Petrol | +25.2% | 13+ years | 82.5% |
| SL | 2006 | Petrol | +24.8% | 13+ years | 82.1% |
| SL | 2007 | Petrol | +24.8% | 13+ years | 82.1% |
| SL | 2000 | Petrol | +23.9% | 13+ years | 81.2% |
| SL | 2003 | Petrol | +23.9% | 13+ years | 81.2% |
| SL | 2002 | Petrol | +23.4% | 13+ years | 80.7% |
| S-Class | 2006 | Petrol | +21.9% | 13+ years | 79.2% |
| E | 2009 | Petrol | +17.7% | 13+ years | 75.0% |
How to read this: A score of "+15%" means the model passes MOTs 15 percentage points more often than the average car of the same age. These are proven results from vehicles that have genuinely aged well.
Proven durability champion
The SL 2005 outperforms the average 13+ years-old car by 26 percentage points, with 1,187 MOT tests proving its reliability.
Early Performers: Strong Start, Unproven Durability
These newer Mercedes-Benz models (3-6 years old) show strong early results, but haven't yet proven long-term durability:
Important caveat: Durability NOT yet proven - these vehicles have not been tested at older ages. Older versions of the same model may tell a different story at 11+ years.
| Model | Year | Fuel | vs Same-Age Average | Tested At | Pass Rate |
|---|---|---|---|---|---|
| GLC | 2018 | Petrol | +8.9% | 5-6 years | 90.1% |
| SLC | 2017 | Petrol | +7.2% | 5-6 years | 88.4% |
| SLC | 2019 | Petrol | +6.9% | 3-4 years | 92.7% |
| E | 2019 | Plug-in Hybrid | +6.7% | 3-4 years | 92.6% |
| S-Class | 2019 | Diesel | +6.6% | 3-4 years | 92.5% |
| GLE | 2016 | Diesel | +6.5% | 5-6 years | 87.7% |
| S-Class | 2017 | Diesel | +6.2% | 5-6 years | 87.4% |
| GLA 200 AMG LINE EDITION A | 2019 | Petrol | +5.6% | 3-4 years | 91.5% |
What this means: These models are performing well in their early years, but we recommend checking the Durability Champions section above to see how older versions of the same model family have fared over time.
Mercedes-Benz A: Year-by-Year Breakdown
The A has 82,826 tests in our database with an overall 87.6% pass rate:
| Year | Fuel | Pass Rate | vs Same-Year Avg | Tests |
|---|---|---|---|---|
| 2021 | Diesel | 94.3% | +3.4% | 401 |
| 2021 | Petrol | 93.8% | +2.9% | 592 |
| 2020 | Petrol | 89.3% | +1.7% | 23,290 |
| 2020 | Hybrid Electric | 88.6% | +0.9% | 6,279 |
| 2020 | Diesel | 88.0% | +0.4% | 6,642 |
| 2019 | Petrol | 87.8% | +1.6% | 26,843 |
| 2019 | Diesel | 85.8% | -0.4% | 16,282 |
| 2018 | Petrol | 85.4% | +1.2% | 371 |
| 2018 | Diesel | 79.0% | -5.2% | 476 |
| 2014 | Petrol | 77.3% | +5.6% | 110 |
| 2014 | Diesel | 68.8% | -2.9% | 359 |
| 2013 | Petrol | 74.9% | +6.6% | 263 |
A verdict: The 2021 diesel model achieves an excellent 94.3% pass rate.
Mercedes-Benz Hybrids vs Petrol vs Diesel
Mercedes-Benz's fuel type comparison shows clear differences in reliability:
| Fuel Type | Average Pass Rate | vs National | Tests |
|---|---|---|---|
| Hybrid Electric | 87.9% | +16.4% | 28,617 |
| Electric | 85.5% | +14.0% | 3,086 |
| Plug-in Hybrid | 82.9% | +11.4% | 10,133 |
| Petrol | 77.9% | +6.4% | 519,760 |
| Diesel | 75.9% | +4.4% | 1,074,144 |
The hybrid advantage: Mercedes-Benz hybrids pass MOTs 10% more often than petrols and 12% more often than diesels.
Mercedes-Benz Models to Avoid
Not all Mercedes-Benzs are reliable. These specific model/year combinations have failure rates well above average:
| Model | Year | Fuel | Pass Rate | Tests |
|---|---|---|---|---|
| CITAN | 2018 | Diesel | 64.3% (-20.7% vs same-age) | 3,539 |
| CITAN 109 PURE CDI | 2020 | Diesel | 67.9% | 1,174 |
| CITAN | 2016 | Diesel | 60.2% (-20.0% vs same-age) | 3,419 |
| VITO 110 PURE CDI | 2020 | Diesel | 69.7% | 511 |
| CITAN | 2017 | Diesel | 63.7% (-18.4% vs same-age) | 3,334 |
| CITAN | 2014 | Diesel | 53.9% (-20.8% vs same-age) | 2,169 |
| CITAN | 2019 | Diesel | 70.6% (-15.8% vs same-age) | 1,810 |
| CITAN | 2015 | Diesel | 61.4% (-15.9% vs same-age) | 2,508 |
| CITAN | 2013 | Diesel | 55.1% (-16.2% vs same-age) | 1,558 |
| VITO | 2019 | Diesel | 75.3% (-11.1% vs same-age) | 8,815 |
Pattern to avoid
Early 2013-2019 diesel CITANs are the models that drag down Mercedes-Benz's average. The VITO 2003 performs 11% worse than the average car of the same age at 13+ years - this is proven poor durability. These vehicles fail MOTs more often than they pass.
What Goes Wrong on Mercedes-Benzs?
When Mercedes-Benzs fail MOTs, these are the most common causes:
| Failure Category | Total Failures |
|---|---|
| 1. Tyres | 117,259 |
| 2. Suspension | 113,201 |
| 3. Lamps, reflectors and electrical equipment | 105,316 |
| 4. Brakes | 91,299 |
| 5. Visibility | 50,652 |
| 6. Noise, emissions and leaks | 43,642 |
| 7. Body, chassis, structure | 22,995 |
Pre-MOT checklist for Mercedes-Benz owners:
- Ensure tyres meet 1.6mm tread requirement
- Inspect suspension bushes and anti-roll bar links
- Check all bulbs (number plate lights are commonly missed)
- Check brake pad thickness and disc condition
- Clean windscreen and check wiper blade condition
Frequently Asked Questions
Our Buying Recommendations
Best If Buying Nearly New
2019-2023 models with highest early pass rates
- Limited data for recent models
Note: Long-term durability not yet proven for these newer models
Best If Buying Used (Proven)
11+ years of proven durability data
- SL 2000-2008: +25% vs same-age (proven at 11+ years)
- S-Class 2006-2011: +18% vs same-age (proven at 11+ years)
- E 2006-2010: +18% vs same-age (proven at 11+ years)
Mercedes-Benz Models to Avoid (Proven Poor)
Proven below average at 11+ years - not just old, genuinely problematic
- VITO 2002-2005: -7% vs same-age (proven poor at 11+ years) (Below average durability at 13+ years)
- CLC 2008-2010: -5% vs same-age (proven poor at 11+ years) (Below average durability at 11-12 years)
- B-CLASS 2006: -5% vs same-age (proven poor at 11+ years) (Below average durability at 13+ years)
About This Data
This analysis uses real MOT test results from the DVSA database, covering 1,662,304 tests on Mercedes-Benz vehicles between 2000 and 2023.
Year-Adjusted Scoring (v2.1): In year-by-year breakdowns, each vehicle is compared against the national average for vehicles of the same model year. This removes the natural bias where newer cars pass more often, allowing fair comparisons across eras.
Evidence-Tiered Durability: We separate "proven durability" (vehicles tested at 11+ years old) from "early performers" (3-6 years old). Only vehicles with proven long-term data are used for durability claims. Age-band comparisons use weighted national averages.
Minimum thresholds: 500 tests for proven durability rankings, 1,000 tests for early performer rankings. Pass rates are calculated as first-time passes, excluding retests.
The overall national average MOT pass rate is 71.51% based on 32.3 million tests across all manufacturers. Year-specific averages range from ~59% (2009 vehicles) to ~88% (2020 vehicles).
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