Skip advert
Advertisement

Mercedes E300 Hybrid vs BMW 520d ED

Has Mercedes made the first fully convincing diesel hybrid with the E-Class? We test it against the BMW 5 Series to find out

Diesel hybrids are still in their infancy, and the previous two we tried failed to deliver on their promise of stunning fuel efficiency and strong performance. Both were from Peugeot, and both were let down by jerky automatic gearboxes, a poor ride and disappointing economy. But surely a company with the engineering might of Mercedes can finally make this combination of powerful diesel and small battery work?

Advertisement - Article continues below

The new E300 Hybrid is aimed squarely at company buyers, and the addition of a lithium-ion battery and electric motor to the drivetrain has turned the E-Class into the cleanest big executive saloon on the market. The boot and spacious interior are both unaffected because the battery is stored beneath the rear seats, and it comes generously equipped to help compensate for a price tag that runs dangerously close to £40,000.

Standing in its way is our current class champ: the BMW 520d EfficientDynamics. The 5 Series is less efficient than the E300 on paper, but it’s cheaper so still competitive in terms of efficiency and, crucially, company car tax bills. After crunching the numbers and racking up the miles, which eco-friendly exec will secure the win?

Verdict

Mercedes has succeeded where others have failed by producing a hybrid model that is not only relevant to the UK market, but also works effectively.

Skip advert
Advertisement
Skip advert
Advertisement - Article continues below

Used - available now

E Class

2020 Mercedes

E Class

92,690 milesAutomaticDiesel2.0L

Cash £11,880
View E Class
E Class

2020 Mercedes

E Class

34,590 milesAutomaticDiesel2.0L

Cash £29,099
View E Class
E Class

2022 Mercedes

E Class

46,027 milesAutomaticDiesel2.0L

Cash £25,899
View E Class
E Class

2020 Mercedes

E Class

50,980 milesAutomaticDiesel2.0L

Cash £23,599
View E Class

Previous petrol hybrids from BMW and Audi have delivered high performance, but poor fuel returns. Yet the E300 easily outmuscled its conventional rival at the track and was also far more efficient at the pumps. However, while the drivetrain is an impressive feat of engineering, the rest of the E-Class is showing its age – and the drab interior and anonymous design mean the revised model can’t arrive soon enough. If these were our only gripes the E300 would be in with a shout in this encounter, but two main flaws prevent it from securing first place.

Lowering the suspension for better aerodynamics has spoiled the ride comfort – not an acceptable compromise for any big exec. The other problem is cost. While the Merc is cheaper to run as a company or private car, the gap isn’t big enough to offset its higher price and steeper depreciation. The BMW is sharper to drive and will offer better value for most buyers, so it remains our efficiency champ by a narrow margin. The classy and spacious interior and bigger boot help it seal victory despite its lack of pace at the track. However, BMW should keep looking over its shoulder, because hybrids are improving all the time.

Skip advert
Advertisement

New & used car deals

Mercedes E Class

Mercedes E Class

RRP £56,650Used from £25,099
BMW 5 Series

BMW 5 Series

RRP £52,285Avg. savings £7,414 off RRP*Used from £20,500
Mercedes C Class
Audi A6

Audi A6

RRP £39,640Avg. savings £8,888 off RRP*Used from £15,490
* Average savings are calculated daily based on the best dealer prices on Auto Express vs manufacturer RRP
Skip advert
Advertisement

Most Popular

New Xiaomi YU7 2025 review: a world-beating new EV to worry the establishment
Xiaomi YU7 - front cornering

New Xiaomi YU7 2025 review: a world-beating new EV to worry the establishment

BMW or Mercedes would do anything to keep the new Xiaomi YU7 from sale in the UK and Europe, and this is why
Road tests
14 Jul 2025
Electric Car Grant in detail: Which cars will get the UK EV discount?
Auto Express creative director Darren Wilson charging the Lexus RZ

Electric Car Grant in detail: Which cars will get the UK EV discount?

The government has set out its plan to help reduce the cost of affordable EVs by introducing a new £3,750 Electric Car Grant for new EVs sold under £3…
News
18 Jul 2025
Electric Mercedes CLA Shooting Brake will keep going long after rivals need to stop
Mercedes CLA Shooting Brake - front action

Electric Mercedes CLA Shooting Brake will keep going long after rivals need to stop

The second of Merc’s new-era EVs is here in the form of an attractive estate with a huge range
News
14 Jul 2025