Used Mercedes S-Class 2014-2020 review

When this iteration of the Mercedes S-Class launched in 2014, it probably stung those at Rolls-Royce and Bentley because some pundits declared this Mercedes to be the best luxury car in the world, and it did so at a fraction of the cost anything made by either British luxury car maker.

But, no matter how good value it was back then, you'd still have needed to be very affluent to buy a new one. Thankfully, with the onset of an all-new 2021-onwards Mercedes S-Class and the benefit of depreciation, you can buy a used example of this technological tour de force for the price of a factory-fresh small car.

Engines & Performance: The lone diesel is the 258bhp S350d, while the petrols range from the 455bhp 4.7-litre V8 in the S500 up to the 530bhp V12-engined S600. There’s also a petrol-electric hybrid known as the 302bhp S400h; a petrol plug-in hybrid called the S500e with 329bhp, as well as a diesel hybrid in the form of the 201bhp S300h.

As part of its facelift in 2018, the S-Class received a set of new engines aimed to maximise efficiency. The 3.0-litre diesel straight six became available in two states of tune: the 286bhp S350d and the more powerful 335bhp S400d. The petrol range benefitted from mild hybrid technology on the 363bhp S450 and revised 451bhp S500 models, while the 482bhp S560e plug-in hybrid gained an electric-only driving range of roughly 30 miles between charges. AMG continued to fit a turbocharged 4.0-litre V8 in the 585bhp S63 and a turbocharged 6.0-litre V12 in the 621bhp S65.

On the road, the S-Class is, for a car of its size and weight, exceptional. Performance with any of the engines in situ is more than adequate. All S-Classes have a nine-speed automatic gearbox that works smoothly and quietly and shifts almost imperceptibly.

Ride & Handling: The S-Class has one of the most cosseting rides of any car in recent times, although not quite so isolating you from imperfections at town speeds as the latest Audi A8. It handles well, too, utilising all the technology it carries to corner with verve, especially so for a luxury limousine.

The steering is precise and you'll find plenty of grip, but where the S-Class shines brightest is in terms of refinement since few other cars can waft like it, making it sublime on the motorway.

Interior & Practicality: Inside, the S-Class is awash with all the kit you could want, never mind need, and provides a great driving position with good visibility. All the major and minor controls are logically placed, work with a well-damped action and have a high-quality feel that few rivals can match. All models get a crisp 12.3in infotainment display that’s intuitive to operate, via touch or a rotary controller.

There’s plenty of space up front and masses in the back, too, especially with the long-wheelbase chassis, which is standard on all variants bar the S350d.

And there’s a large boot that's more than adequate for a week’s worth of holiday luggage, although the S500e and S560e plug-in hybrids have smaller boots (395 litres and 410 litres) because their batteries required take up some space.

Trims & Equipment: Trim levels tend to be assigned to whichever engine you choose, but some give you the option of AMG or AMG Line trim. Both are more than well-equipped, as you might imagine, with AMG Line giving you keyless start and entry, cruise control, 19in alloy wheels, front and rear parking sensors, a rear-view camera, metallic paint, adaptive LED headlights, heated, electrically adjustable leather front seats with lumbar adjustment and a memory function, the Command Online infotainment system with two 12.3in screens, sat-nav, and even Apple CarPlay, Android Auto and a wireless smartphone charger are available in post facelifted examples from 2018 onwards.

Interested in buying a used Mercedes S-Class? Visit our Used Cars For Sale pages to find lots of cars listed at great prices.

For a car that came in at a small fortune new, you might be surprised to learn that you can pick up an early 2014 example for as little as £15,000. It will probably be an ex-chauffeur car with a galactic mileage on it, though, so we'd suggest that you spend closer to £20,000 for something with a below-average to average mileage for the year and a full service history.

For a 2018 model, prices near £30,000 and often exceed that, with 2020 models pushing £40,000 – that's the last of this breed, although there are a few that strayed into 2021.

If you fancy one of the V8s, have upwards of £24,000 – that'll be the S500. The plug-in hybrids will set you back a few grand more.

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MPG: The most economical pre-facelift S-Class is the S500e plug-in hybrid, with an NEDC combined fuel consumption of 100.9mpg. However, unless you do a lot of short journeys and utilise every available charging station, you’re unlikely to come anywhere near those figures in reality. Next up is the S300h hybrid with 61.4mpg. Again, you’re unlikely to match that excellent figure in daily use, but you might still achieve a similar figure to the S350d diesel, which claims 52.3mpg if motorway work makes up the majority of your driving.

Facelifted cars received revised engines and some got mild hybrid technology to improve economy figures. There were also tested under the new WLTP fuel economy rating system, which is why some models appear to have become less efficient. The S560e is still the best, with 122.8mpg, followed by the S450 and S500 mild hybrid petrols, which both achieve a combined 36.2mpg. AMG customers will have to take poor economy figures (24.4mpg for the S63 and 18.6mpg for the S65) on the chin. Both the S350d and S400d get a combined figure of 44.1mpg, which is lower than before but much more realistic.

CO2 emissions: Not all of the engine options were available prior to the 1 April 2017 tax rule changes, so we're only focusing on those that were here. The lowest is the petrol plug-in hybrid S500e at 65g/km, followed by the diesel hybrid S300h at 120g/km and the regular diesel S350d with 151g/km. The petrol hybrid S400h is next with emissions of 154g/km, but things get significantly worse with the pure petrol models since the S500 puts out 207g/km, with the S63 and S65 AMG models having the worst figures of 237g/km and 279g/km, respectively.

Road tax (VED): Tax for cars registered before the changes of 1 April 2017 came into force will vary depending on the CO2 output, so will favour the plug-in hybrid and hybrid model and to a certain extent the diesel, but still at a fairly high rate. Cars registered after that date will pay the new flat rate, which is a little less, as well as a supplementary charge for cars that cost over £40,000 new, which all S-Classes do. Current rates are £190 per year for the road tax for petrol and diesel cars, £180 per year for hybrids and £415 per year for the luxury car tax – the latter of which lasts from the second to sixth year of the car's life.

Servicing: Servicing costs will be large, but Mercedes offers a number of service plans that offer more convenient ways of paying, including direct debits. Unfortunately, whether you opt for a plan or just pay for each individual service, the costs tend to be greater than those of rivals such as Audi and BMW.

Engine: Choose the S350d and you’ll be getting one of the sweetest and quietest diesel engines around. You really would be hard pushed to tell that there was a diesel engine beneath its bonnet.

Specification: We’d seek out the AMG Line trim, because this keeps costs down (in relative terms) and gives you all the goodies a car like the S-Class deserves and expects. We’d also look for the long-wheelbase version.

Our favourite Mercedes S-Class: S350d L AMG Line

The latest (post-2017) Audi A8 is even quieter than the S-Class and rides just as well, which is really saying something. Previous A8s were pretty good, too, although there was a slight gruffness to their diesel engines and their ride left a little to be desired. They make a fine used buy, though, with good-value models widely available.

The latest BMW 7 Series is a technical tour de force, with almost as much luxury and safety kit as the S-Class. Used examples now make for secure buys, and the driving, interior and standard kit all match the expectations of buyers in this market. Earlier generations aren’t quite as impressive, but find one that's reasonably priced and you’ll still enjoy luxury motoring on a budget.

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Interested in buying a used Mercedes S-Class? Visit our Used Cars For Sale pages to find lots of cars listed at great prices.