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Mercedes-Benz E-Class vs Audi A6

Figures updated

The Mercedes-Benz E-Class and Audi A6 are two of the UK's most popular executive cars. We compare the W214 (2023–) E-Class and the C9 (2025–) A6 on price, size, boot space, performance, safety and running costs, plus how reliable each has been across 353,599 real MOT tests.

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The short answer

Pick the Mercedes-Benz E-Class for the bigger boot, or the Audi A6 for the lower price, the better MOT record and lower fuel costs.

FigureMercedes-Benz E-ClassW214 (2023–), 4-door saloonAudi A6C9 (2025–), 4-door saloon
Price and practicality
Price newUK list prices, across the range£57,170 to £88,520June 2026 price listfrom £54,060October 2026 price list (best)
Body4-door saloon4-door saloon
Seats55
BootSeats up / folded540 litres (best)492 litres
Length4,949mm4,999mm
WidthWithout mirrors1,904mm1,875mm
Height1,468mm1,452mm
Performance
Power197–313 PS (best)204–299 PS
0–62mph6.4–7.6 sec6.0–8.2 sec (best)
Safety
Euro NCAP ratingTests get tougher each year★★★★★ (2024)★★★★★ (2024)
Economy and emissions
Fuel typesDiesel, Petrol, Plug-in hybridElectric, Hybrid, Petrol, Plug-in hybrid
Official economyVersions of this generation23.3–60.1 mpg36.2–55.4 mpg
CO211–276 g/km32–178 g/km
Electric range–329–462 miles
Running costs at 7,500 miles a year
Petrol or hybrid171.8p a litre, today's UK average£1,764 (33.2 mpg)£1,450 (40.4 mpg) (best)
Diesel198.4p a litre£1,412 (47.9 mpg)–
Electric, charged at home26.3p per kWh standard tariff–£548 (4 mi/kWh)
Cheapest version to fuelWhichever fuel costs least£1,412 (diesel)£548 (electric)
Car tax a yearCars registered from April 2017£200£640 in years 2–6 for versions listed over £40,000£200
Reliability from real MOT tests
Reliability score133Well above average155Well above average (best)
Failed MOT first time (ages 3–20)22.5%20.9% (best)
Failed at 3 years old13.3%9.5% (best)
Failed at 5 years old14.7%11.2% (best)
Failed at 10 years old25.1%20.5% (best)
Most common MOT faultTread depth (2.7% of tests)Tread depth (2.9% of tests)
Fails more than average onWheels (2.9×)Nothing stands out
MOT tests analysed230,974122,625
About the cars
TypeExecutive carExecutive car
Owners' average miles a year10,60011,000
On sale2023 on2025 on

Green marks the better figure where the difference is more than 3%. Reliability figures cover every version of each model tested in the year. Running costs use the typical official economy of recent versions (WLTP where available); real-world economy is usually a little worse for every car.

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Frequently asked questions

›Is the Mercedes-Benz E-Class or the Audi A6 more reliable?

The Audi A6. Like for like on age and mileage, the Mercedes-Benz E-Class fails its MOT about 17% more often (reliability scores 155 and 133, where 100 is average). 20.9% of Audi A6s and 22.5% of Mercedes-Benz E-Classes failed first time in 2024.

›Which is bigger, the Mercedes-Benz E-Class or the Audi A6?

The Audi A6 is 50mm longer (4,999mm against 4,949mm). The Mercedes-Benz E-Class has the bigger boot: 540 litres against 492.

›Which is cheaper to buy, the Mercedes-Benz E-Class or the Audi A6?

The Audi A6: new prices start at £54,060, £3,110 less than the Mercedes-Benz E-Class (from £57,170). These are manufacturer list prices; dealers and brokers often sell for less.

›Which is cheaper to run, the Mercedes-Benz E-Class or the Audi A6?

Comparing petrol versions, the Audi A6 costs about £314 a year less to fuel at 7,500 miles (£1,450 against £1,764), using typical official economy and current UK average fuel prices.

›Which is safer, the Mercedes-Benz E-Class or the Audi A6?

Euro NCAP gave the Mercedes-Benz E-Class 5 stars (2024) and the Audi A6 5 stars (2024). Euro NCAP makes its tests tougher every few years, so ratings from different years aren't directly comparable.

›Should I buy the Mercedes-Benz E-Class or the Audi A6?

Pick the Mercedes-Benz E-Class for the bigger boot, or the Audi A6 for the lower price, the better MOT record and lower fuel costs. The comparison above sets out price, space, performance, safety, running costs and reliability side by side.

Sources: manufacturers' UK specifications and price lists and Euro NCAP (listed on each model's page); DVSA anonymised MOT tests 2024 (Open Government Licence v3.0); Vehicle Certification Agency car fuel data, © Crown copyright, VCA cannot accept liability for its accuracy; fuel prices from the GOV.UK Fuel Finder scheme. Photos from Wikimedia Commons, credited under each picture.