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Real MPG: most efficient prestige SUVs
What are the most efficient prestige SUVs? What Car?'s Real MPG tests reveal what fuel economy you can really expect from a car...
As their title suggests, premium SUVs aim to offer an upmarket experience. Extra badge appeal, finer fixtures and fittings, more power... the list of potential gains is long, and can sometimes include more fuel-efficient engines.
But just how fuel efficient? The official government MPG figures published in sales brochures can tempt you into buying a particular car, but those results are often hard to achieve in the real world.
That's where What Car?'s Real MPG tests come in. Conducted to strictly regulated parameters in the UK, they reflect what we believe should be achievable by most drivers, as an average, in town, on rural routes and for motorway driving.
Below, we count down the 10 most economical prestige SUVs we've tested to date, and explain more about our exclusive test methodology.
The most fuel-efficient prestige SUV:
1. Mercedes GLA 220d Diesel
Real MPG Average 46.5mpg | Town 34.4mpg | Motorway 44.5mpg | Rural 60.7mpg
Inevitably, diesel rules the roost for highest mpg figures in a class of typically heavier SUVs. However, it's worth noting that we have hybrid and petrol options in our top ten if you keep scrolling down. It's also worth bearing in mind that the latest diesel engines are incredibly clean relative to even just a few years ago, and that's reflected by the fact they avoid the most punishing tax levies. The 220d is powerful, pulling strongly through the rev range and working slickly with the standard eight-speed automatic gearbox.
Read our full Mercedes GLA review or see our latest Mercedes GLA deals
Read on to find out how we work out a car's Real MPG, and see more of the prestige SUVs which performed well in our tests, as well as the models which will cost you the most to run.
How we test a car's Real MPG
In order to ensure that all of our Real MPG tests are comparable, they are undertaken in strict laboratory conditions. As a result, variables such as weather or traffic conditions don't affect our figures.
However, in addition, in order to make them as reflective of real-world conditions as possible, the route the car 'drives' while on the test rig has been mapped according to real routes in town, on rural roads and on the motorway.
Adding a further layer of rigour, before any car goes on the test rig it's, tyre pressures are checked, its internal climate control is set to 21 degrees (or at the midway point if it has manual air conditioning) and the fan speed's lowest setting is selected. No headlights or electrical equipment are switched on.
Using an exhaust connection we measure tailpipe emissions every second, with our overall Real MPG figure taken from an average of the results.
2. Audi Q2 1.4 TFSI 150 Petrol
Real MPG Average 45.3mpg | Town 37.6mpg | Motorway 42.0mpg | Rural 56.3mpg
This version of the Q2 is no longer on sale, its engine having been replaced by a newer unit. However, we'd recommend considering one if you are buying used, because its Real MPG of 45.3 figure is impressive even against more modern technology and still good enough to make it the most efficient petrol-powered prestige SUV that we've driven. Overall, the Q2 represents classy buy, majoring on its interior quality, tidy handling and terrific resale values.
Read our full used Audi Q2 (2016-present) review or see our latest Audi Q2 deals
3. Volvo XC40 D3 Diesel
Real MPG Average 42.9mpg | Town 32.1mpg | Motorway 40.1mpg | Rural 57.1mpg
Another engine that is no longer on sale, this time a diesel. It fell out of favour as fewer buyers opted for diesel power and Volvo decided to switch its attentions to promoting electric and hybrid powertrains, but that doesn't override the fact that it is a terrific unit that still deserves consideration as a used buy. The XC40 is a former What Car? Car of the Year and continues to receive top rankings against rivals when it's rated by our testers.
Read our full used Volvo XC40 (2017-present) review or see our latest Volvo XC40 deals
4. DS 4 Crossback 1.2 Puretech 130 Petrol
Real MPG Average 42.6mpg | Town 34.7mpg | Motorway 38.9mpg | Rural 54.7mpg
We're big fans of the DS 4's entry-level 129bhp PureTech 130 petrol engine; it packs enough punch for most buyer’s needs and returns an impressive Real MPG figure of 42.6mpg. It's especially suited to town driving, however, delivering its power smoothly and picking up from speed effortlessly, except when it is worked really hard. The standard eight-speed gearbox helps ensure the engine stays in its most efficient rev band most of the time.
Real MPG Average 41.3mpg | Town 56.8mpg | Motorway 35.0mpg | Rural 44.1mpg
This version of the Lexus NX is the highest placed hybrid in our lis, combining electric power with a 2.5-litre petrol engine to achieve its impressive Real MPG average of 41.3mpg. The combination also makes for quite a quick car; the four-wheel drive NX 350h's official 0-62mph time of 7.7sec leaves many rivals' in the shade (it is 8.7sec in front-wheel drive). The automatic gearbox also helps to keep engine revs down and economy up.
Read our full Lexus NX review or see our latest Lexus NX deals
5=. Audi Q5 2.0 40 TDI Diesel
TRealrue MPG Average 41.3mpg | Town 30.7mpg | Motorway 38.9mpg | Rural 54.6mpg
In order to boost fuel-efficiency, this entry-level diesel engine for the Audi Q5 uses mild hybrid technology, and it clearly does so to good effect, given this result. Adding further lustre, the diesel engine is a strong all-rounder, pulling effortlessly from low revs and delivering silky smooth acceleration as you gather speed. Little wonder this car and engine combination has also done well in our Tow Car Awards, although hauling a caravan will bring those fuel economy figures down considerably.
Read our full Audi Q5 review or see our latest Audi Q5 deals
7. Lexus UX 2.0 Petrol Hybrid
Real MPG Average 40.4mpg | Town 32.5mpg | Motorway 36.9mpg | Rural 51.2mpg
The UX's hybrid system combines a 2.0-litre petrol engine and an electric motor, producing a sprightly 182bhp in total. As a result, it's pretty quick and punchy if needed - more so, even, than some diesel-powered rivals. That it can combine that with strong fuel efficiency is therefore all the more impressive. Although the UX is a hybrid, you can't plug it in (instead it charges on the move), so its all-electric capability is very limited, but if you are gentle with the accelerator in stop-start traffic it will run using the electric motor alone.
Real MPG Average 40.1mpg | Town 29.4mpg | Motorway 38.7mpg | Rural 52.0mpg
The Cupra Formentor is classified as a coupé SUV – an inherently sporty shape that doesn't usually imply fuel efficiency. However, at least in the case of this entry-level petrol model (our testers' favourite in the range), that's misleading. This impressively thrifty engine and gearbox combination has 148bhp; enough to ensure that you don't have to break a sweat to get around, but not so much that you're tempted to enjoy rushes of riotous acceleration and ruin your fuel economy.
Read our full Cupra Formentor review or see our latest Cupra Formentor deals
9. BMW X2 2.0 Diesel
Real MPG Average 39.6mpg | Town 27.0mpg | Motorway 38.1mpg | Rural 55.3mpg
With 187bhp this is quite a powerful diesel engine for a relatively small car, but as well as giving the X2 impressive acceleration, it also means it has plenty of power in reserve when you're driving with more restraint – good news for fuel economy. An eight-speed automatic gearbox is the perfect partner to this engine, ensuring that the revs are kept down unless you're really pushing on.
Real MPG Average 39.2mpg | Town 31.0mpg | Motorway 36.6mpg | Rural 49.9mpg
Unlike the second-placed Q2 in this list, this engine is available to buy new today. The 148bhp 1.5-litre petrol unit is one step up from the entry-level petrol engine in the range and is noticeably punchier than the '30' that sits below it. Given the Q2's premium billing, if you have the budget then we'd recommend spending the the extra. It comes with a six-speed manual gearbox as standard, but for a little extra you can have a seven-speed automatic, called S tronic, as tested here.
Read our full Audi Q2 review or see our latest Audi Q2 deals
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