Mercedes-Benz C-Class

When you first see the latest Mercedes-Benz C-Class - the sixth-generation version of Merc's upper-medium model, it's slightly underwhelming. It doesn't really stand out, although the sleek exterior design looks stylish enough - it's basically a scaled-down version of theirange-topping S-Class. In fact, the only giveaway, that this is a plug-in hybrid, is the extra fuel filler on the left of this car.

Move inside, and things are largely the same, although you can't miss the C300e's 11.6in iPad-like touchscreen that curves out of the centre console for the latest MBUX infotainment system. Another debut from the latest S-Class, although we'd argue it looks more impressive in the smaller C-Class. A complex system that has been designed around personal profiles. After getting into the car, you sign in and the car adjusts to your perfect driving position - it even puts on your favourite radio station. Considering MBUX's complexity, we're grateful for the fact that it's easy to use.

Elsewhere, the C-Class's interior is attractive, well-designed, and high-quality. Rear legroom is better than the last-generation car but feels tighter than it should be - even for children. The most noticeable interior compromise for the C300e, is the observable drop in boot space - 140 litres in fact - thanks to the hybrid battery. Although still practical, it totals 315 litres.  

The main fleet interest points with the latest C-Class are the availability of plug-in hybrid versions, like the one we're comparing here. However, the rest of the diesel and petrol engines are mild hybrids, with the 48V system, allowing the C-Class to coast with the engine off and offering a small power boost when accelerating.

The C300e we're focussing on here is powered by a 204hp, 2.0-litre petrol turbo engine combined with a 24.5kWh battery and 95kW electric motor, equalling an impressive 313hp. So, the performance figures are good, but company car drivers are going to be keener on the 5% BIK charge, emissions as low as 12g/km, with Mercedes claiming an average economy of a scarcely believable 565mpg, and 68 miles range on electric power alone. This is 27 miles more than its closest rival, the BMW 330e, can manage. It is credible too, as when we had this car, we saw 40 miles, on our longest 228-mile round trip, which was mostly covered on the motorway, and it wasn't fully charged when we set off. 

So, we know the PHEV version of the petrol C-Class is an impressive car, but how does it stack up against other plug-in hybrid rivals, such as the BMW 330e, Citroen C5X and even the Volkswagen Passat - read on to find out which comes top. 

PHEV versions of Mercecdes' C-Class have previously scored well for residuals, and the new model carries on that tradition, as it comes first with its 40.88% figure. Its closest rival, the second most expensive model of the four, the BMW 330e, coming second. According to the P11D figure, the Mercedes is the most expensive of the group, and it has the third highest depreciation figure of the four at £28,764. The Mercedes is followed again by the BMW (£27,721), Citroen (£26,544) and in last place is the Volkswagen at £29,845.

According to fuel figures supplied by Key Resources, this plug-in Mercedes is capable of 43.5mpg, which is more than the BMW and Volkswagen, but not quite enough to better the Citroën from the top position with its 44mpg figure. Most surprising here, is the fact that the BMW finishes last, but all this plug-in group are very close in terms of their figures. 

Where you see the benefit of the C300e's 69-mile EV-only range, is in terms of its Benefit in Kind (BIK) figure and at 5%, is significantly lower than the rest of the group's 12% figure. Overall, the Mercedes scores well enough - especially in terms of BIK. But that's not enough here for the C300e to score the best cost per mile figure, as its high list price has an effect, putting this car in second place.

Mercedes-Benz C300e AMG Line 

P11D: £48,655

CO2 (tax):12g/km (5%) 

BIK 20/40% a month: £41/£81

Fuel consumption: 43.5 mpg

National Insurance: £1,098

First year VED: £0

Subsequent VED: £155

Engine size/power: 1,999cc + 24.5kWh/313hp

AFR: 17p

Residual value: 40.88%

Depreciation: £28,764

Fuel costs: £6,469

SMR: £2,405

Cost per mile: 62.73p

BMW 3 Series

The C-Class runs it close, but the seventh-generation BMW 3 Series remains king of the premium cars in our opinion. Indeed, it won the Best Premium Car award for the fourth year running at the Business Car Awards 2022.

Whatever 3 Series you choose, you won't be disappointed by the driving experience. In addition to the performance, other driving highlights are the precise steering and tidy handling. The ride and refinement are well-judged, too. 

Our favourite and a key choice for fleets, is the BMW 330e plug-in, which combines a 181hp 2.0-litre petrol engine with an 11.15kWh battery and 88kW electric motor, which together equal up to 35 miles of EV range, a total of 288hp and BIK starting at 12%.

Just facelifted, the biggest facelift change is to the interior, with the addition of tech borrowed from another of our winners - the BMW i4. Now fitted with a huge, curved display made of two screens, running an intuitive infotainment system that can be interacted via voice or gesture control. Like the i4, the 3 Series also benefits from all the features of the MyBMW app. 

Thanks to the smaller 35-mile EV range, the BMW achieves the same 12% BIK figure as the Citroen and Volkswagen. The 330e's figures are close to the other cars in this group, and despite a mid-placed depreciation figure, its high price, biggest SMR figure and lowest economy figure mean our favourite can only finish third here.

BMW 330e M Sport  

P11D: £46,075

CO2 (tax): 31g/km (12%)

BIK 20/40% a month: £92/£184

Fuel consumption: 40.35mpg

National Insurance: £2,422

First year VED: £0

Subsequent VED: £155

Engine size/power: 1,998cc + 12kWh /249hp

AFR: 17p

Residual value: 39.84%

Depreciation: £27,721