You can still have a combustion-powered A6 Saloon. Jonathan Crouch drives the C9-era version.

Background

It was Audi way back in the '80s, who set the trend for aero-optimised upper mid-sized executive saloons. The Audi 100 of that era evolved into the first-generation C4-era A6 of 1994 and through four further A6 generations, Ingolstadt has explored sleek styling in this segment more than any other brand. Culminating in this C9-generation A6 Saloon; the most slippery combustion-powered Audi to ever enter production. The 'combustion-powered' caveat here is important; the completely separate all-electric A6 e-tron model that sells alongside this car is more slippery still. That model, like this one, is also available in Avant estate form. But it's the four-door combustion A6 we concentrate on here.

Driving Experience

In a market where rivals are starting to wonder whether they should have been quite so hasty in dropping diesel power, this A6 Saloon celebrates the black pump, reserving arguably its most sophisticated engine tech for the TDI version, which uses the company's usual four cylinder 2.0-litre unit. As with the A5, this means installation of the brand's MHEV plus system, which offers a big step forward from Ingolstadt's previous mild hybrid technology. For one thing, it uses a much bigger e-motor, providing 24PS and 230Nm of torque. For another, it acts as more than just a starter generator, also able to drive the car on its own at parking speeds. Plus, using a brake-by-wire set-up, the system can also regenerate energy at up to 25kW, so the compact lithium battery will always be topped up. As we said, the 2.0 TDI unit in question is a familiar one - and the quattro 4WD system it must be paired with is familiar too. Total output is 204PS, which is the same as the alternative four cylinder engine on offer, the 2.0 TFSI petrol. This can only be front-driven and makes 62mph in 8.3s en route to 144mph, respectively 1.3s and 5mph slower than the diesel. The UK won't get the 3.0 V6 TFSI petrol unit offered on the continent. But we do get a PHEV e-Hybrid powertrain, which is based around the 2.0 TFSI four cylinder petrol unit and offers 299PS and up to 70 miles of EV range from its 25.9kWh battery (20.7kWh usable). That's a little better than a BMW 530e, but a little worse than a Mercedes E 300 e. The A6 e-hybrid offers 450Nm of torque and 62mph takes 6.0s en route to 155mph. Two operating modes are available: 'EV' and 'hybrid'. In EV mode, the plug-in hybrid models run solely on electric power, while in hybrid mode, the hybrid management system maintains a specific charge level as needed in order to save enough electrical energy for later use. Across the line-up, Audi claims drive dynamics have been improved with this C9-generation design. To that end, there's a stiffer torsion bar, stiffer control arm bushings, a more rigid steering rack and increased front camber. All of this is supposed to improve steering feel and road feedback. Plus the sleeker bodywork should help refinement.

Design and Build

You'd recognise this as an A6. Possibly (though not necessarily) because Audi says it has modelled the back of this Saloon on the curved rear end which marked out the very first dedicated A6 design, the C5 version of 1997. You'll have your own view on that; for us, it looks a bit more like the C7 model of 2011. Whatever the provenance, it's sleekly styled - and very different to the A6 e-tron (which can't be had as a saloon). Audi's used steel instead of aluminium for the boot lid because it can be shaped more easily - in this case into edging with a subtle spoiler. There's also a hidden light bar and pricier versions get OLED light tech with configurable graphics. The three-box shape is uber-slippery (0.23Cd) and the front end is of course the same as that of the A6 Avant estate we've reviewed separately, with an imposing grille and bonnet lip. The front-of-cabin experience is of course just the same as that of the A6 Avant. Which means the most premium-feeling cabin in the segment, its architecture similar to the A6 e-tron (developed at much the same time). Which means a huge central fascia panel called the 'digital stage' that houses an 11-inch instrument screen and a 14.5-inch central infotainment monitor in a single curved housing. There's no lower centre stack screen as in the old model, but customers can specify an optional 10.9-inch passenger side display. As long as you don't mind shiny black trimming, you should feel it to be all quite high-end, with high quality soft-touch finishes and leather-like materials wherever you look. We're pleased to see the retention of some proper physical controls around the dashboard too. Rear seat space is impressive; even a lanky passenger stuck behind a tall driver will have plenty of leg room. Out back, there's 492-litre boot - just 11-litres less than the Avant, though this figure falls to 452-litres if you choose the e-Hybrid PEV version.

Market and Model

Let's get to the prices for this A6 Saloon, which at the time of our test in Summer 2026 were starting from around £52,000, just under £2,000 less than the Avant version. At the time of this review, pricing for this A6 e-hybrid was starting from around £62,000. Which incidentally, is about the same as you'll pay for an all-electric A6 e-tron, if you're comparing against that, though the e-tron only comes in either hatch or Avant estate forms. With this A6 Saloon, as with the A6 Avant, there are the usual 'Sport', 'S line', 'Black Edition' and 'Vorsprung' trim levels. In terms of the value proposition against this model's traditional rivals, you're looking at needing much the same sort of money for one of these that you'd need for a comparable BMW 5 Series; but you'd be saving around £4,000 on a comparable Mercedes E-Class. Audi though, thinks that this A6 offers the strongest value proposition in the segment - and there's certainly plenty included as standard. Like Matrix LED headlamps, power-folding mirrors, a powered boot lid, Adaptive cruise control, an automatic parking system and an anti-theft alarm. Inside, there's Twin leather upholstery, 3-zone deluxe climate control, a surround view camera system, a 10-speaker 180-watt Audi Sound set-up and heated front seats. Mid-level 'S line' trim upgrades the base 'Sport' version's 18-inch wheels to smarter 19-inch rims; and adds sports suspension, sports front seats, a Sport leather steering wheel and rear privacy glass. 'Black Edition' spec gets a black-themed exterior styling package with 21-inch wheels and dinamica microfibre cabin trimming. Finally the top 'Vorsprung' versions get a panoramic sunroof, Digital Matrix LED headlights, OLED tail lamps, a front passenger MMI display and a Bang & Olufsen 3D Sound System with headrest speakers. Unless you stretch right up to top spec, you'll need to find £2,650 extra to get the 'Technology Pack' that's probably the key extra with this car. This includes a head-up display, increased charging capacity for the USB ports and that Bang & Olufsen premium sound system with 3D sound that we mentioned. The pack also includes Audi's 'ambient lighting package pro' set-up, which means you get the useful 'dynamic interaction light' which arches around the top of the dash and illuminates in different colours to warn you of safety issues, drive mode selections or 'phone settings. With 'Sport' or 'S line' trim, many customers will also want to pay extra for larger 20-inch alloy wheels; and you can also add a tow bar.

Cost of Ownership

Expect up to 55.5mpg on the combined cycle and up to 133g/km of CO2 from the TDI diesel; obviously, you'll do a little worse than that with the 2.0 TFSI petrol version (up to 40.4mpg and 159g/km). The key engineering efficiency development with this C9-era A6 Saloon is, as we told you in our 'Driving' section, the new 'MHEV plus' mild hybrid system that features on the diesel versions. This is based on a 48-volt on-board electrical system that supports the combustion engine and reduces CO2 emissions while increasing performance. Its added powertrain generator (the 'PTG') enables electric driving components that contribute to a reduction in fuel consumption. The 'MHEV plus' system offers advantages in CO2 emissions compared to the previous MHEV set-up. Over the WLTP driving cycle, these total up to 10g/km of CO2 in the 2.0 TDI. The PTG can also add up to 24PS of electric power to the output of the combustion engine. When decelerating, the PTG feeds energy back into the battery at up to 25kW. As a result, purely electric manoeuvring and parking are possible to a limited extent. Thanks to the option of using an electric air conditioning compressor, the air conditioning system can also be operated when the vehicle is stopped at traffic lights and the combustion engine is switched off. With the integrated and blending-capable brake control system, the brake pedal and the brake hydraulics can be completely decoupled. In models with the 'MHEV plus' system, it achieves the necessary deceleration without using the friction brakes thanks to regenerative braking. This means that deceleration is initially achieved solely by recuperation. The friction brakes only kick in when the brake pedal is pressed harder. The brake feel remains unaffected by this. With the e-Hybrid PHEV model, combined cycle economy is rated at up to 128.6mpg, with CO2 emissions rated at up to 50g/km. Maximum AC charging power is 11kW (down on the 55kW a rival Mercedes E-Class PHEV offers) and if the battery is completely empty, a full recharge to 100 percent can take as little as 2.5 hours. Recuperation performance has also been improved over the old A6 TFSI e. The degree of recuperation intensity in electric driving mode (EV -mode) can be adjusted to three different levels using paddles on the steering wheel. The new A6 e-hybrid runs on electric power for as long as possible to fully utilise the available battery charge to the driver's destination. The vehicle recovers energy automatically when this function is activated. This is based on route data stored in the navigation system.

Summary

Half a decade ago, this is the kind of large executive saloon we'd have thought would have been replaced by an EV by now. As it turns out, we do have a replacement EV model - the A6 e-tron - but Audi, like its competitors, can't afford to restrict itself to the all-electric market right now; not in this segment anyway. And for a business customer still not quite ready to make the EV switch, this C9-era A6 Saloon offers an appealing dose of vorsprung durch technic, with a bit of old and a bit of new in its swept-back styling. The need for differentiation from an A6 e-tron suggests the need for the 'A7' badge Audi originally had planned for this model. But in almost every way that really matters, it's very much an A6.