Skip advert
Advertisement

Mercedes C180K BlueEFFICIENCY

New engine and body tweaks help the c-class clean up its act

Find your Mercedes C-Class
Compare deals from trusted partners on this car and previous models.
Or are you looking to sell your car?
Value my car
Fast, no-nonsense car selling
Value my car

Even though it has arrived relatively late at the eco party, Mercedes’ new BlueEfficiency system is superb. This C180K is a great example of a refined and fuel-efficient saloon that doesn’t demand compromises of the driver. Mercedes says petrol power could mount a resurgence in the executive sector – and this car is so efficient, it could be right.

Advertisement - Article continues below

There’s no doubt BMW stole a lead over Mercedes with its economical EfficientDynamics models. Now, though, the three- pointed star is set to respond with its own line of fuel-sipping BlueEFFICIENCY machines.

First to go on sale is the entry-level C180K. Instead of employing the stop-start system favoured by BMW, Mercedes has chosen to downsize. The C-Class’s 1.8-litre engine has been replaced by a 1.6-litre, still boosted by a supercharger. It produces 156bhp and 230Nm of torque from 3,000rpm.

There is plenty of pulling power and drivers can move quickly through the gears – which is key to the new car’s efficiency. Mercedes has fitted a dashboard indicator telling you when to change up. And even when the light advises you to select fifth at 30mph, the car copes well.

In addition, lower suspension, energy-saving tyres and more aerodynamic door mirrors help make the C-Class more slippery.

The manufacturer claims the newcomer returns an average of 44.8mpg and emits 149g/km of CO2. This isn’t quite as good as a 3-Series, but represents an improvement of nearly 10 per cent on the standard C-Class.

Adding to the appeal is the fact the BlueEFFICIENCY costs no more than the 1.8, plus is £50 a year cheaper to tax and has better predicted residuals.

Rival: BMW 3-Series
with the EfficientDynamics system, the 3-Series adds strong fuel economy and low emissions to its list of talents. It’s already in the top 10 of the UK sales charts with its blend of agility and quality.

Skip advert
Advertisement

New & used car deals

Mercedes C Class

Mercedes C Class

RRP £17,570Used from £11,700
BMW 3 Series

BMW 3 Series

RRP £14,520Avg. savings £6,140 off RRP*Used from £9,700
Mercedes A Class

Mercedes A Class

RRP £20,350Used from £16,495
BMW 4 Series

BMW 4 Series

RRP £24,799Avg. savings £6,110 off RRP*Used from £17,495
* Average savings are calculated daily based on the best dealer prices on Auto Express vs manufacturer RRP
Skip advert
Advertisement

Most Popular

BYD offices raided over Land Rover Defender copycat claims
New BYD Ti7 - front 3/4

BYD offices raided over Land Rover Defender copycat claims

Two of the Chinese firm’s offices in the Netherlands were raided in the summer by bailiffs acting on behalf of JLR, it has emerged
News
9 Nov 2026
It’s time for Tata to step aside and let the Chinese take over at Jaguar Land Rover
Opinion - Freelander 8

It’s time for Tata to step aside and let the Chinese take over at Jaguar Land Rover

Mike Rutherford thinks the joint-venture between Chery and Jaguar Land Rover could be a match made in heaven
Opinion
8 Nov 2026
BMW i3 vs Mercedes C-Class Electric vs Hyundai Ioniq 6: big test for the 3 Series EV
BMW i3 vs Mercedes C-Class Electric vs Hyundai Ioniq 6 - front tracking

BMW i3 vs Mercedes C-Class Electric vs Hyundai Ioniq 6: big test for the 3 Series EV

The new electric BMW 3 Series takes on Mercedes’ latest C-Class and the updated Hyundai Ioniq 6 in a premium EV showdown
Car group tests
10 Nov 2026