Audi A6 vs BMW 5 Series

Big executive cars need to offer a comfortable ride and keen company car tax costs. Does the Audi A6 or BMW 5 Series do it better?...

Author Avatar
What Car? team
21 February 2015

Audi A6 vs BMW 5 Series

The contenders

Audi A6 2.0 TDI 190 Ultra SE S tronic

Minor updates have cut CO2 emissions of this automatic version to just 109g/km.

BMW 520d SE auto

BMW’s big exec has a new engine and comes seriously well equipped as standard.  

The BMW 3 Series is still Britain’s most popular executive saloon, but if you were thinking about buying one right now you’d be wise to reconsider. That’s because, believe it or not, a similarly well-equipped 5 Series – the company’s larger, more premium saloon – will actually cost you less to own privately, and a mere £3 a month more to run as a company car.

Is the 5 Series the very best of its breed, though? To find out, we’re pitting it against its long-term archrival, the Audi A6. Both cars have just been updated; their CO2 outputs have been cut to just 109g/km and, even in entry-level SE trim, they now come with all the standard luxuries that typical well-heeled customers will expect.

What are they like to drive?

Both cars have 2.0-litre diesel engines that produce exactly the same amount of power and torque, so it’s hardly surprisingly there’s little to split them when it comes to performance. The rear-wheel-drive BMW is slightly quicker away from the mark, but the front-wheel-drive Audi edges it when you sink your right foot and accelerate from 30-70mph.

Bigger differences are evident when you’re driving more sedately, because while the BMW’s eight-speed automatic gearbox is quick to respond and always picks the right gear for the situation at hand, the Audi’s seven-speed gearbox often hesitates when you go to accelerate. It doesn’t blur gearshifts quite as seamlessly at low speeds, either.

Ride comfort is more important than sporty handling to most executive car buyers, who will be spending much of their time on the motorway, but whichever your priority it’s the 5 Series that’ll impress you most. It does a brilliant job of smoothing over patched-up surfaces and potholes around town, and stays settled and composed on the motorway.

Not that the Audi is even bordering on uncomfortable. Yes, you feel more of the bumps as they pass beneath the car, but they’re still smothered well compared with most other premium saloons.

Our test BMW came fitted with optional Variable Damper Control (£985), which effectively lets you stiffen and soften the suspension by pressing a button. While the more comfortable setting gives a smooth ride, you’ll want to switch to Sport mode on twisting country roads, because the whole car immediately tightens up. It leans less through corners and its body doesn’t bounce as much over dips and crests.

Meanwhile, the A6 stays just as upright as the 5 Series through corners, but its front wheels lose grip earlier through tight turns and its steering doesn’t provide you with as much feedback as the BMW’s.

It’s a similar story when it comes to refinement, because the 5 Series is the quieter car at a steady 70mph cruise. That’s mainly because less road noise makes its way into the cabin, but there’s marginally less wind noise, too. 

Accelerate hard and you’ll realise that the Audi’s engine is slightly smoother and quieter, but both are seriously refined compared with most four-cylinder diesels.

What are they like inside?

The Audi leads the way on interior quality. From the brushed aluminum inserts to the chunky, well-damped buttons and switches, the A6 simply exudes class. That said, you’d have to be a serious pedant to find anything to complain about in the BMW; everything looks suitably high-class and all of the controls feel substantial.

Both cars have logically laid-out dashboards that are easy to fathom, although the 5 Series does have the more intuitive infotainment system. You control both systems using a rotary dial and a selection of shortcut buttons positioned between the front seats, but the BMW’s on-screen menus are that little bit better thought out.

You sit higher up in the Audi, so while its seats are tough to fault for comfort, some will prefer the 5 Series’ lower, more cocooned driving position. That said, it’s easier to adjust the seats in the A6. The BMW’s are decidedly fiddly unless you fork out £950 for electric adjustment.

Whichever car you buy, we’d recommend you add adjustable lumbar support (£275 on the 5 Series and £295 on the A6). This important feature – which really should be standard on cars costing more than £30k – will help keep your posture good on longer journeys, helping prevent lower back pain and potential spinal injuries in the long term. 

These are both big cars, so whichever you choose you’ll have no trouble carrying four lanky adults in comfort. There’s marginally more rear head- and legroom in the BMW, but its chunky transmission
tunnel makes life relatively uncomfortable for the fifth person sitting in the middle.

There’s next to nothing in it for outright boot space, and both cars’ load bays are similarly long and tall. The BMW’s is broader at its widest point (right at the back), but it also tapers to a narrower point farther into the car, and you have to pay £335 extra for split-folding rear seatbacks, which come as standard on the A6.

What will they cost?

This isn’t an area that’s likely to help you decide, because both cars will cost you near enough the same to buy and run.

Taking into account the changes to benefit-in-kind tax over the next three years, a 40% rate taxpayer will have to sacrifice around £8000 of their salary to run either as a company car. If you’re buying privately
the differences are also small, because while Audi dealers are prepared to offer bigger discounts, the 5 Series is predicted to hold on to more of its value after three years. 

There’s also little to split the two when it comes to servicing or insurance bills, and while we hadn’t True MPG-tested either car at the time of writing, their predecessors (which had very similar mechanicals) both averaged around 50mpg in real-world driving.

Despite costing only a couple of thousand pounds more to buy than a relatively basic BMW 3 Series, both of these saloons come with all the luxuries you’re likely to want or need, including leather seats,
sat-nav, climate control and xenon headlights. You also get cruise control, automatic light and wipers, keyless start and front and rear parking sensors, and BMW even throws in heated front seats, which
cost extra on the Audi.

According to Euro NCAP, the 5 Series is the safer car; it outscored the A6 on adult and pedestrian protection, and matched it for child protection. Both cars come with six airbags and a tyre pressure-monitoring system as standard, but you have to pay extra for automatic emergency braking on both.

Our verdict

The 5 Series just gets better and better with age. It’s always been brilliant to drive and suitably plush inside, but it now makes a surprising amount of financial sense, too – particularly for company car drivers – thanks to its lower CO2 emissions and surprisingly generous standard kit list.

The new A6 appeals to the wallet just as much, and also comes very well equipped. However, it isn’t as brilliant to drive as its German rival, and its infotainment system isn’t quite as user-friendly, so it has to finish second.


BMW 520d SE auto

Brilliant to drive; refined; well equipped; spacious

Against Adaptive dampers cost extra; so does automatic braking 

Verdict The best executive car in the world


Audi A6 2.0 TDI 190 Ultra SE S tronic

Sumptuous interior; smooth engine; lots of standard kit

Against Steering; gearbox isn’t as smooth

Verdict Still a very fine executive car