In association with MotorEasy
Most reliable Mercedes models - and the unreliable ones to avoid
In our annual Reliability Survey, we ask readers to rate the dependability of cars aged up to five years old. Here are most and least reliable Mercedes models...
The Mercedes-Benz brand has a long heritage, having been founded in 1926. Its roots go back even further, to 1886, when Carl Benz created the Benz Patent-Motorwagen, which is widely recognized as the world's first true automobile.
In recent decades, it has been hailed as the brand that brings cutting-edge technology to the automotive sector - it was the first company to introduce electronic stability control (ESP) in 1995, and in 2021 it showcased the Hyperscreen, an edge-to-edge digital dashboard powered by AI, in the S-Class luxury saloon.
Its current line-up comprises a mix of internal combustion engined models, such as the A-Class and E-Class, and the EQ range of pure electric models, ranging from the EQA electric family SUV to the EQS luxury seven-seater.
The brand has had some issues with reliability, and was joint 22nd out of 30 brands, alongside fellow German rival Audi, in our latest rundown of the most reliable car brands with a score of 90.6%. The previous generation E-Class is the most dependable model, and the current C-Class the poorest performer.
Here we're looking at reliability data for Mercedes models aged up to five years old. Reliability information for older models is in our most reliable used cars feature.
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Most reliable Mercedes models
1. Mercedes E-Class (2016-2024)
Reliability rating 97.3%
Most common faults: Non-engine electrics 8%, brakes 4%
Average repair cost: 100% £0
Typical time off road: 50% one day to a week, 25% less than a day, 25% more than a week
Although the E-Class saloon isn't quite as sumptuous, and pricey, as the S-Class, it's an eminently elegant, spacious model that offers a superb blend of comfort and advanced technology. It's available in a range of bodystyles, including the estate, coupé, cabriolet and a mildly off-road estate called the All-Terrain. Diesel engines range from the entry-level 148bhp E 200 d to the six-cylinder 335bhp E 400, and there are two petrol plug-in hybrid options.
In spite of all its gadgetry, the E-Class is pretty reliable. Owners told us that only 16% of their cars went wrong, and all of those could still be driven. All faults were put right by Mercedes for free, and the only downside is that most issues took more than a day to fix.
2. Mercedes GLB (2020-2026)
Reliability rating 96.0%
Most common faults: Non-engine electrics 10%, bodywork 5%, engine electrics 5%, interior trim 5%, sat-nav/infotainment system 5%
Average repair cost: 100% £0
Typical time off road: 50% one day or less, 33% one day to a week
Launched in 2020, the GLB is closely related to the Mercedes B-Class MPV, but it's an SUV that's roughly the same size as its two similarly priced rivals, the Audi Q5 and BMW X3. Its advantage over them is that it comes with seven seats. It comes with a choice of two petrol and two diesel engines, ranging from the economical 148bhp 220d to the fire-breathing AMG-fettled GLB 35.
Although it was bothered by a high proportion of faults - 29% of the examples reported on went wrong - all of those involved could still be driven. Minor electrical niggles were the most common concern, and half of the problems were remedied in a day or less, and another third in less than seven days. Even better, Mercedes covered the cost of putting things right in all instances.
3. Mercedes GLC (2015-2023)
Reliability rating 94.6%
Most common faults: 12-volt battery 5%, non-engine electrics 4%, air-con 2%, electric motor 2%, engine 2%, engine electrics 2%, sat-nav/infotainement system 2%
Average repair cost: 100% £0
Typical time off road: 43% more than a week, 38% one day or less
The GLC is Mercedes' large SUV rival to the Audi Q5, BMW X3 and Land Rover Discovery Sport. It is well equipped with a stylish interior and a range of punchy engines. Most versions have a diesel engine under the bonnet, and the four-cylinder versions are less refined than those of rival models. The ride is also harsher than alternatives, so it's worth checking this out before you buy.
Our survey data shows that 21% of GLCs had a problem, with the 12-volt battery and other electrical systems the main culprits. Four out of five faulty cars could still be driven, and Mercedes paid for all rectification work. It's just a shame that 43% of cars were out of action for more than a week.
Reliability rating 94.3%
Most common faults: Air-con 8%, bodywork 8%, fuel system 8%
Average repair cost: 100% £0
Typical time off road: 72% one day or less, 14% one day to a week, 14% more than a week
The GLA is based on the same underpinnings as the A-Class saloon, which is a good thing because that means it shares that model's wide range of engine options, smartly appointed interior and user-friendly MBUX infotainment system. The GLA 200 petrol is enough if you tend to drive mostly in town, but the 220d diesel is a better all-rounder if you carry a car full of occupants or cover long distances. The 250e is best suited to company car drivers.
According to our survey, 25% of the cars reported on went wrong, but 86% of them remained driveable. Issues were split evenly between the air-con, bodywork and fuel systems. Nearly three-quarters of cars were fixed in a day or less, and only 14% were off the road for more than a week.
5. Mercedes EQA (2021-present)
Reliability rating 94.1%
Most common faults: Air-con 7%, EV battery pack 7%, bodywork 3%, brakes 3%, electric motor 3%, sat-nav/infotainment system 3%, suspension 3%
Average repair cost: 100% £0
Typical time off road: 50% more than a week, 40% one day or less
The EQA is the pure electric version of the Mercedes GLA family SUV. It has a growing number of rivals, including the Genesis GV60, Kia EV6 and Smart #1. The front-wheel-drive 250+ version is the one to pick if range is your priority, because it can travel up to 345 miles under official figures. The dual-motor, four-wheel drive 300 and 350 versions can only manage 266 miles.
The EQA's fault rate is similar to the GLA, at 23%, with 90% of the affected vehicles remaining driveable. The most common causes of concern were the EV battery pack and the air-con system. Although Mercedes covered the cost of all repairs, getting things sorted out was fairly slow, with 50% of cars stuck in the garage for more than a week.
6. Mercedes A-Class (2018-present)
Reliability rating 93.4%
Most common faults: Interior trim 8%, non-motor electrics 6%, bodywork 5%, suspension 5%, sat-nav/infotainment system 4%, air-con 3%, 12-volt battery 3%, engine electrics 3%, suspension 3%
Average repair cost: 100% £0
Typical time off road: 49% one day or less, 24% more than a week
The fourth-generation A-Class is classy, comfortable, good to drive and packed with technology, helping it to be regarded as one of the best premium-badged options in the family car class. The petrol-powered A200 is our top choice, because it's more sprightly than the entry-level A180 and reasonably frugal.
Nearly a third (32%) of the cars reported on went wrong, but 94% of them could still be driven. Trim, bodywork and electrical issues were the main headaches. The good news is that nearly half of the cars affected were in and out of the garage the same day, and that Mercedes paid for all the fixes.
7. Mercedes CLA (2018-2025)
Reliability rating 92.7%
Most common faults: Non-engine electrics 14%, 12-volt battery 10%, bodywork 5%, brakes 5%, fuel system 5%, sat-nav/infotainment 5%
Average repair cost: 100% £0
Typical time off road: 56% one day to a week, 22% a day or less, 22% more than a week
The used-only CLA is a four-door coupé version of the A-Class saloon. That means it has a coupé silhouette with a swooping roofline, but most of its oily bits are shared with its more traditionally styled cousin. It has the same smart-looking interior as the A-Class and the same choice of engines. Secondhand prices are competitive, making it an appealing used buy.
Only 19% of the CLAs in our survey had any issues, and all could still be driven. Electrical foibles were the main concern, followed by problems with the 12-volt battery. Mercedes paid for all the necessary work, and just over half of the cars with issues were back on the road in less than a week.
8. Mercedes C-Class (2014-2021)
Reliability rating 88.8%
Most common faults: Engine electrics 7%, non-engine electrics 7%, engine 3%, gearbox 3%, interior trim 3%, sat-nav/infotainment 3%, steering 3%, suspension 3%
Average repair cost: 67% £0, 22% more than £1500
Typical time off road: 60% more than a week, 20% a day or less, 20% one day to a week
The previous-generation C-Class faces stiff competition in the executive car class from the Audi A4 and the BMW 3 Series. However, it stands out for its high level of comfort, efficient engines and strong image. There are three choices if you're after a fuel-efficient model: the C350e plug-in petrol hybrid, C300h diesel hybrid, or the C300de plug-in diesel hybrid.
The C-Class is a little more prone to problems than its coupe sibling, the CLA - 23% of the examples in our survey went wrong, but 80% of them could still be driven. Getting things put right could be slow - nearly two-thirds of cars were in the workshop for more than a week - and only 67% of repair bills were covered by Mercedes, leaving some owners with bills topping £1500.
9. Mercedes EQC (2019-2024)
Reliability rating 86.5%
Most common faults: EV battery pack 18%, motor electrics 12%, bodywork 6%, interior trim 6%, non-engine electrics 6%, suspension 6%
Average repair cost: 100% £0
Typical time off road: 50% one day to a week, 40% more than a week
The EQC was Mercedes' first built-from-scratch electric vehicle, when it went on sale back in 2019, and it sits in the popular large SUV category. Good sales mean there are plenty of them to choose from used. Refinement and long-distance comfort are where the EQC excels, and its performance is more than enough to keep speed freaks happy. However, it doesn't have the range of the similarly priced Jaguar I-Pace, and it doesn't handle as well as that rival.
Worryingly, the EV battery pack was the most common area cited by owners as problematic, followed by the electrical systems surrounding the motor. Overall, owners told us that 24% of their cars had issues, but only 30% of them couldn't be driven. Mercedes paid for all faults to be fixed, but 40% of owners had to wait more than a week to get their car back.
Most unreliable Mercedes models
1. Mercedes C-Class (2021-present)
Reliability rating 76.3%
Most common faults: Engine electrics 14%, air-con 10%, fuel system 10%, non-engine electrics 10%, hybrid battery pack 5%, bodywork 5%, brakes 5%, electric motor 5%, engine 5%, sat-nav/infotainment system 5%
Average repair cost: 100% £0
Typical time off road: 38% more than a week, 38% one day to a week
The latest C-Class isn’t looking as sturdy as the previous model; 43% of cars built from 2021 onwards had a glitch, compared with 23% for the 2014-2021 generation. Failures occurred across a range of areas, including the air-con, engine, fuel system, gearbox and non-engine electrics.
Thirty-nine percent of faults were serious enough to stop cars from being used. Only 19% of cars were put right in a day or less, and 38% were in the workshop for more than a week. At least owners were spared the expense of unexpected bills; all repairs were performed for free.
2. Mercedes GLE (2019-present)
Reliability rating 82.0%
Most common faults: Non-engine electrics 22%, air-con 9%, interior trim 9%, engine 9%, 12-volt battery 4%, bodywork 4%, brakes 4%, engine electrics 4%, exhaust 4%, sat-nav/infotainment system 4%, suspension 4%
Average repair cost: 100% £0
Typical time off road: 45% more than a week, 40% one day to a week
A high proportion of latest-generation GLE models were afflicted by a range of electrical issues, including problems with the infotainment and air-con systems, as well as with the 12-volt battery, engine, exhaust and interior trim.
Overall, 43% of GLE owners reported at least one fault. Only 15% of the affected vehicles couldn’t be driven until repaired, but 45% were being worked on for more than a week. Just 15% of faults were sorted within a day or less. The only saving grace is that Mercedes-Benz paid for all remedial work to be performed.
Reliability of Mercedes models aged up to five years old
| Rank | Make and model | Score |
| 1 | 2016-2024 Mercedes E-Class | 97.3% |
| 2 | 2020-2026 Mercedes GLB | 96.0% |
| 3 | 2015-2023 Mercedes GLC | 94.6% |
| 4 | Mercedes GLA (2020-present) | 94.3% |
| 5 | Mercedes EQA (2021-present) | 94.1% |
| 6 | Mercedes A-Class (2018-present) | 93.4% |
| 7 | 2019-2025 Mercedes CLA | 92.7% |
| 8 | 2014 -2021 Mercedes C-Class | 88.8% |
| 9 | 2019-2024 Mercedes EQC | 86.5% |
| 10 | Mercedes GLE (2019-present) | 82.0% |
| 11 | Mercedes C-Class (2021-present) | 76.3% |
To read the reliability data for other car classes follow these links:
Most and least reliable cars overall
Most reliable car brands
Most reliable family cars
Most reliable executive cars
Most reliable luxury cars
Most reliable small SUVs
Most reliable family SUVs
Most reliable large SUVs
Most reliable seven-seaters
Most reliable electric cars
Most reliable electric SUVs
Most reliable sports cars
Most reliable diesel cars
Most reliable petrol cars
Most reliable hybrid cars
How the research was carried out
To compile the What Car? Reliability Survey, conducted in association with MotorEasy, we asked thousands of car owners to give us the lowdown on how reliable their car had been over the previous 24 months.
First we asked them to tell us if the car had suffered a fault, and, if so, how much each problem had cost to put right and how long it had kept the car off the road. The responses for these two factors were weighted and added up for each make and model, enabling us to create a unique reliability rating for each.
The latest What Car? Reliability Survey contains responses from 29,967 people, giving us enough data to report on 199 models aged up to five years old from 31 different car brands.
About the report author
Claire Evans has been a motoring journalist for more than 30 years, working on consumer issues for a great deal of that time. After a stint as the advice columnist for Carweek magazine in the 1990s, she also spent six years working on motoring content for Which?. It is here she oversaw the running of the charity's annual used car reliability survey.
Claire launched the What Car? Reliability Survey in 2017, and since then has helped thousands of buyers choose the most reliable new cars and SUVs, as well as the most dependable used cars.
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