True MPG: Most and least efficient luxury cars and SUVs
What Car?'s True MPG tests show what fuel economy you can really expect from a car. Here, we reveal the best and worst-performing luxury models we've ever tested...
The official MPG figures published in car sales brochures can tempt you into buying a particular model, but those results are often misleading. So, to show you the sort of fuel economy you can expect in real-world use, What Car? does its own True MPG tests.
They're carried out under strictly controlled conditions to ensure accuracy and repeatability, and simulate a mix of town, rural and motorway driving.
As a result, they reflect what's achievable if you drive gently and stick to speed limits but don't resort to any unrealistic fuel-saving techniques.
Find out more about how we test for True MPG >>
In this slideshow, we count down the top 10 luxury cars and luxury SUVs among all those we've tested for MPG, and reveal which models cost the most – and the least – to run.

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