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Mercedes-BenzCLS (2018-2021)

Used only
Large
Petrol/Diesel/Mild hybrid

£30,294Typical price

Test score

where to buy or sell

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The third-generation Mercedes-Benz CLS arrived in 2018 as the most sophisticated version of the company's pioneering 'five-door coupé' design. Is the CLS a case of style over substance, or is this a great all-round luxury car to beat the Audi A7 and BMW 6 Series Gran Coupé? Read our full Mercedes-Benz CLS review to find out.

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What's included?

What is it?
What's it great at?
What's it like to drive?
How reliable are Mercedes-Benz cars?
How comfortable and spacious is it?
How economical is it to run?
How safe is it?
Is there anything I should look out for?
Should I buy it?

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KEY TEST RESULTS
Comfort and practicality
Brand reliability 0-4 years

Nov 2023Last checked by Which?
Sept 2018First reviewed by Which?
May 2018Released

The overall Which? test score is made up of the following star ratings, all determined by our rigorous lab tests.

How we test cars

19 Oct 2023

Ease of driving

Overall
Visibility
Smoothness of power delivery
Driving stability
Cabin layout

How we test ease of driving

To find out how easy a car is to drive, we assess cars across a number of areas from visibility and handling to the layout of the cabin and how smoothly the engine delivers its power.

Performance

Overall
In-gear acceleration
Brakes

How we test performance

We test braking distances and whether the effectivess of the brakes fade with repeat use. Performanc is based on in-gear acceleration.

Comfort and practicality

Overall
Entry and exit
Seat comfort
Ride quality
Quietness
Seat space
Boot space (large cars, SUVs and MPVs)

How we test comfort and practicality

Comfort and practicality includes how easy it is, or not, to get in and out of the car and the maximum height of occupants. We also measure road, wind and engine noise and assess how well the car deals with bumps from large potholes to jittery surfaces like cobble stones.

Euro NCAP

How we test euro ncap

Any car that receives a rating of three stars or less from Euro NCAP is made a Don't Buy. If a car has been available for more than four years and has not been tested by Euro NCAP, it cannot be a Best Buy.

Which? safety

Brand reliability 0-4 years

Overall
Electric car reliability
Plug-in hybrid reliability
Petrol reliability
Diesel reliability

How we test brand reliability 0-4 years

Our reliability ratings are based on the feedback from tens of thousands of UK motorists, as collected in our annual Which? car survey. We divide all reliability feedback into three age groups: cars aged up to four years, five to nine years, and 10 to 15 years.

Brand reliability 5-9 years

Overall
Diesel reliability

Brand reliability 10-15 years

Overall
Petrol reliability
Diesel reliability

General
Class	Large
Luxury	Yes
Convertible	No
Availability	Used only
Used price	£30,294 - £39,927
Fuel type	Petrol/Diesel/Mild hybrid
Tested fuel efficiency	41.5mpg
Length	4,988mm
Width (excluding wing mirrors)	1,890mm
Width (including wing mirrors)	2,070mm
Height	1,435mm
Driver max height
Second row passenger max height
Boot space with seats up
Boot space with seats down
Number of seats	5
Folding rear seats	Yes
Isofix attachments	Yes
Turning circle	11.95 m
On sale date	01 May 2018
Lowest pence per mile cost	£16.71

Latest tested engine
Engine name	CLS400d Coupe AMG Line 4Matic 9GTronic
Fuel type	Diesel
Capacity and power	2.9-litre (340hp)
Transmission	9-speed automatic
Driven wheels	Four-wheel-drive (4WD)
Fuel tank capacity	50 litres
Tested fuel economy: City / Out of town / Motorway (mpg)
Tested fuel economy: Combined (mpg)
Cost per mile	16.71p per mile
Cost of filling tank	£76
Monthly fuel cost
Annual fuel cost
NOx level	Very low
CO level	Very low
CO2 at tailpipe/tank-to-wheel (TTW) (g/km)	179
Well-to-wheel (WTW) CO2 (g/km)	215
Official fuel economy: NEDC	47.9
Official Euro emission level	Euro 6d-Temp
Braked tow load (KG)	1900kg
Unbraked tow load (KG)	750kg
Engine test date	25 May 2018
Test programme	2017

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All new and used car advice

Mercedes-BenzCLS (2018-2021)

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pros

cons

What's included?

How we test cars

Ease of driving

Performance

Comfort and practicality

Euro NCAP

Which? safety

Brand reliability 0-4 years

Brand reliability 5-9 years

Brand reliability 10-15 years

How this product's score compares with other new and used cars we've tested

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Kia

Renault

Seat

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Mercedes-BenzCLS (2018-2021)

where to buy or sell

pros

cons

What's included?

Test results

Specifications

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Suggested Alternatives

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