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Mercedes S-Class (2014-2020) review - MPG, CO2 and running costs

Despite the high purchase prices, the S-Class needn't cost a fortune to run

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With prices starting comfortably in excess of £72,000, the S-Class isn’t exactly cheap to buy; and, if you get a bit friendly with the options list, the price can rise to well over £100,000. However, despite the price tag, the S-Class shouldn’t cost you the earth to run.

Under the official testing regime, the S 350 d returns more than 50mpg and emits 139g/km of CO2, while the S 500 L averages just over 40mpg, and even the S 63 returns 32.1mpg. The S 560 e mild-hybrid is claimed to be the most economical, returning 113mpg. Those are impressive figures, given how big the car is and how fast it can go.

Depending on how you use the car, of course, those figures could be very different. The economy will certainly plummet, if you delve into the available performance, for example. 

Insurance Groups

Insurance for the S-Class range starts at group 46 for the S 350 d, and goes up with your potential to go faster. The S 500 is in group 48, and the two Mercedes-AMG models are in group 50. That may look pretty hefty, but in fact the groupings are no worse than for comparable models from BMW and Audi. 

Depreciation

All luxury cars have a reputation for losing value on an epic scale. If ever that’s not true in relative percentage terms, then it certainly is in terms of hard cash. The basic principle seems to be that the more you spend on your new S-Class, the more you stand to lose when you sell the car on.

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In best-selling S 350 d form, though, we think the new S-Class should match the previous model’s 44 per cent residual value after three years.

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