2026 Mercedes S580e L | UK Review

The most comprehensively improved S-Class ever makes it to the UK - we try the 585hp flagship

By Nic Cackett / Monday, 9 November 2026 / Loading comments

Imagine a present where the Mercedes EQS was a roaring success. Hard to do, right? But in that reality, one far removed from our own, a properly lauded all-electric luxury saloon might have dissuaded Mercedes from bothering with such a far-reaching S-Class facelift, one touted to deliver 2,700 alterations. Instead, the EQS descended like a lead balloon through the glass floor, its tiny audience presumably defeating even Mercedes most pessimistic projections; so much so that, for a time, the firm stopped building them altogether. After four years on sale, just 26 are available in the classifieds, which anecdotally suggests they are as numerous on UK roads as Corvettes.

For those of us inclined to think most EVs an imperfect and untimely solution to a politically motivated issue, the EQS was perfect evidence of early OEM adopter folly: Mercedes already built arguably the best luxury saloon, it needed to be electrified in 2021 like a dog needs a cappuccino maker. The market’s reluctance to embrace the model is presumably one of the factors that ordained not just the most comprehensive update of the S-Class ever attempted, but also the introduction of a new flat plane crank V8 engine to power it.

Naturally, UK customers haven’t been allowed to sample the pleasure of eight cylinders in Mercedes’ flagship for yonks - and that’s likely because the S-Class appeals less to big spending car enthusiasts in this country (who, after all, have Bentley and Rolls-Royce right on the doorstep), and more to powerfully built company directors who like to be chauffeured about the place in something less ostentatious and nakedly expensive to refuel. First-hand experience of the previous V8-powered model has suggested they are missing out, but for now the plug-in hybrid S580e occupies the top rung of the powertrain ladder.

This combines Mercedes’ turbocharged 3.0-litre straight-six (outputting the same 449hp it does in numerous AMG models) with a 163hp electric motor housed in the nine-speed transmission for 585hp overall. You can have the same engine unaided by battery power in the S500, which trades chunkier straight-line performance for lower weight - though obviously you don’t get 60-odd miles of EV range. Assuming you (or more likely, a staff member) has remembered to plug it in, that is. Inevitably, the hybrid enjoys a preferential tax bracket; inevitably, its claimed lower running costs are thwarted if you don’t keep the battery topped up.

As is often the case with hybrids, the real-world experience is a mixed bag. Despite the failure of the EQS to float people’s boat, electric motors are hardly misaligned with a silent, swanky driving experience - meaning you’re unlikely to complain about the way the S580e ghosts away from a standing start, nor how it glides conveniently to A-road speeds. How could you when there’s a water-cooled supercomputer (not really, but let’s humour Mercedes here), absorbing the input of so many cameras, radar sensors and ultrasonic measurers to help smooth out the road ahead? Sure, not all of them are dedicated to improving the ride quality - most cater for Level 4 autonomous driving - but rarely does a chassis convince you so completely that your journey is being systematically reduced to a GPS-informed algorithm.

As you might expect, there is an unreal quality to the way the Airmatic suspension deftly counters the jigsaw puzzle that is every knobbly B road, so plainly is its vertical stiffness being modulated for the prevailing conditions - but you tend to forgive its disinterest in realism or driver engagement; the S-Class would much rather be the twenty featherbeds between you and the proverbial pea. Thus it makes sense that the control surfaces are glassy and the silence deafening, too: the S580e’s default mode is a millpond-style serenity. It’s like driving a pair of moccasins.

Which is great for as long as you’re content to let battery power carry the load. But only a saint would potter for so long in a car that claims to output nearly 600hp; before long you’ll find yourself prodding for the place in the throttle map where the engine comes alive. The transition is achieved smoothly enough - though not without the S580e clinging onto silent running for a beat too long - and, to listen to, the straight-six (a vocal presence in other applications), is as distant as a colonial cousin. At no point does the flagship feel stupendously quick, though perhaps you wouldn’t notice if it were, the car being so preoccupied with isolating you from your surroundings.

It’s something of a shame then that having worked so hard to suspend you in its low-stress bubble, the new S-Class does such a mediocre job of convincing you it’s truly the place to be. Quite when OEMs will learn that screens, no matter how prodigious in inches nor how well integrated into a single piece of glass, do not, in fact, equate to ‘luxury’ is a continuing mystery, as is the idea that both front passengers need to be able to actually see their phones while they charge. Probably you’ll get to grips with the UI in short order, and most of what you really need is easy enough to find, but Mercedes might’ve won many more admirers if its imagination went beyond pandering to Chinese tastes.

Or conceivably it thinks the view from the front seats is less important than the back. And by virtue of the fact that the S580e comes to the UK in ‘L’ format exclusively, that instinct might not be misplaced. At any rate, it’s deeply pleasant in the capacious rear, where the dreary fixed touchscreens ahead of you can be ignored completely, leaving you free to recline sun lounger-style, while the world drifts noiselessly by. Presumably some customers like to do work back there, but in the AMG Line Premium Plus trim tested, the S-Class works best as a leather-lined decompression chamber. Pop your bonce on the pillowy headrests and you’ll be power napping in minutes.

Alternatively, if you do ever feel inclined to give your driver the afternoon off - and can be bothered to locate the S850e’s sportier drive modes - there is enough going on underneath to keep you awake. You’ll have to meet the steering halfway and obviously expect to take a large bite out of your MPG, but with the six-pot much more heavily involved and the chassis (subtly and very sensitively) knuckling down, you ought to have no issues sweeping confidently between the sighted corners of your driveway. To suggest it ever really comes alive would be overstating a very soft-edged sort of heavyweight vigour. But with four-wheel steering prominent among its many, many integrated gizmos, the latest S-Class is certainly not devoid of dynamic bandwidth.

Ultimately, the main issue with selecting the hybrid is less about the car itself and more about the model directly adjacent to it. We haven’t driven the mild hybrid (i.e. predominately straight-six-powered) S 500 in the UK yet, although dispensing with plug-in status - and the accompanying 22kWh battery - saves it more than 300kg. Hence a 0.1-second difference in 0-62mph times despite it taking a 100-odd horsepower haircut. And the 185-litre improvement in boot space. And the £6k saving on list price. Which might not be of much interest to the powerfully built company directors amongst us, given its much loftier 191g/km CO2 emissions. But I bet you the cheapest EQS it’s the sweeter S-Class to drive.

SPECIFICATION | 2026 MERCEDES-BENZ S580e L

Engine: 2,999cc, straight six turbo, 22kWh battery, electric motor
Transmission: 9-speed automatic, all-wheel drive
Power (hp): 585
Torque (lb ft): 553
0-62mph: 4.4secs
Top speed: 155mph
Weight: from 2,618kg
MPG: up to 97.5 (up to 61 miles electric range)
CO2: from 66g/km
Price: £122,425 (AMG Line Premium; AMG Line Premium Plus £130,675, AMG Line Premium Plus Executive £135,675)