2026 Audi A6 vs 2025 Mercedes-Benz S-Class

The 2025 Mercedes-Benz S-Class was a nod to the era when elegant sedans dominated the roads. With its 208-inch length, this four-door vehicle maintained a commanding presence, offering a sleek and traditional luxury form. The seventh-generation S-Class, introduced in 2021, retained its evolving character with a more aerodynamic style, featuring smoother body creases, a larger grille, and retractable door handles. The long hood and wheelbase suggested a spacious passenger compartment, with the U.S. market exclusively offering the longer wheelbase model. Inside, the S-Class boasted a horizontal dashboard layout, interrupted by digital displays that seemed out of place. However, the cabin was adorned with premium materials, including supple leather and attractive trim elements, showcasing Mercedes' exceptional construction quality.

The 2026 Audi A6, while not visually striking, was handsome with its trademark "singleframe" grille and fender flares inspired by the Quattro rally car. The LED headlights featured a pixelated effect with programmable signatures, while the taillights were repositioned to accommodate programmable lights displaying different icons. The A6 was available in Premium, Premium Plus, and Prestige trims, with the redesigned model offered only as a sedan. The S Line Black Optic Package added sporty elements, while the Sport Plus Package included 21-inch wheels and rear-axle steering. The Audi Exclusive Design Package offered two-tone Nappa leather seats, but the interior materials felt disappointingly bland and cheap, even in top-spec models.

The 2025 Mercedes-Benz S-Class offered four models, each distinguished by its powertrain. The entry-level S 500 featured a turbocharged 3.0-liter inline-six engine, producing 442 horsepower and 413 pound-feet of torque, with a 0-60 mph time of 4.5 seconds. The S 580 upgraded to a twin-turbo 4.0-liter V8, delivering 496 hp and 516 lb-ft, achieving 0-60 mph in about 4.25 seconds. All models came with a nine-speed automatic transmission and 4Matic all-wheel drive, with mild-hybrid systems in the S 500 and S 580. The AMG S 63 E Performance topped the lineup with a plug-in hybrid system, combining a twin-turbo V8 and an electric motor for 791 hp and 1,055 lb-ft, reaching 0-60 mph in 3.3 seconds. The S 580e plug-in hybrid, with a six-cylinder engine and electric motor, offered 503 hp and 553 lb-ft, with an estimated 48 miles of electric range and a 0-60 mph time of 4.8 seconds. The S-Class delivered a smooth and comfortable ride, with well-managed body roll and impressive maneuverability, thanks to rear axle steering.

The 2026 Audi A6 featured a turbocharged 3.0-liter V6 engine, producing 362 horsepower and 406 pound-feet of torque, paired with a seven-speed dual-clutch transmission and standard quattro all-wheel drive. This engine, shared with the S5 sedan, allowed the A6 to achieve a 0-60 mph time of 4.5 seconds, quicker than base models of the BMW 5 Series and Mercedes E-Class. The A6's powertrain provided an energetic driving experience, though there was noticeable hesitation from the transmission under heavy throttle. The Sport Plus Package included a sport rear differential and steel-spring suspension, enhancing handling but compromising ride quality. Rear-axle steering improved maneuverability, while the progressive steering rack offered precision, albeit with artificial heft in Dynamic mode. The A6 excelled on highways but was less suited for spirited driving, with noticeable tire noise on rough surfaces.

The 2025 Mercedes-Benz S-Class featured curvaceous front seats resembling classic wingbacks, providing ample space and comfort for larger occupants. Standard heating, ventilation, and massage functions enhanced long road trips. Storage space was adequate, with moderately sized cupholders, door pockets, and a center armrest bin. The rear seats were equally accommodating, with optional features like heating, ventilation, and massage functions, as well as an executive passenger-side rear seat with a power footrest. Cargo capacity for the S 580e was 8.1 cubic feet, while other models offered 12.8 cubic feet, with a center pass-through door for longer items.

The 2026 Audi A6, 2.4 inches longer than its predecessor, maintained the same wheelbase, resulting in unchanged passenger space. The panoramic glass roof increased front-seat headroom by two inches, while rear-seat headroom and legroom remained similar. The A6 offered comparable space to the BMW 5 Series, with rear-seat climate controls and USB-C ports. Heated and ventilated front seats were standard, with optional sport seats featuring massagers. The conventional trunk provided 13.5 cubic feet of cargo space, more than the Cadillac CT5 and Mercedes E-Class, but less than the BMW 5 Series.

The 2025 Mercedes-Benz S-Class came equipped with a 12.3-inch digital instrument panel, a 12.8-inch infotainment touchscreen, native navigation with augmented reality video overlays, voice recognition, and a Burmester surround-sound system. The Pinnacle trim added rear-seat amenities like an infotainment-system tablet, voice controls, and an entertainment system with two 11.6-inch displays. The infotainment system offered crisp graphics and quick responses, but the capacitive touch controls were frustrating to use. The voice-control technology was highly accurate, though dependent on an Internet connection.

The 2026 Audi A6 featured the Digital Stage setup with an 11.9-inch digital instrument cluster and a 14.5-inch touchscreen, along with an optional 10.9-inch front-passenger touchscreen. The latest MMI infotainment system had oversimplified layouts, but improved voice recognition and standard wireless Apple CarPlay and Android Auto helped. Audi planned to roll out a new interface with an integrated dashcam and a new steering wheel. The optional Bang & Olufsen 3D audio system included headrest speakers for navigation directions.

The 2025 Mercedes-Benz S-Class offered standard advanced safety features, including forward collision warning, automatic emergency braking, adaptive cruise control, blind-spot monitoring, lane-keep assist, automated lane-change assist, evasive steering assistance, automatic reverse braking, a semi-automated parking system, and a surround-view camera system. The Pinnacle trim added rear-seat side and seatbelt airbags. The adaptive cruise control was particularly smooth and reliable, though crash test results were unavailable.

The 2026 Audi A6 included standard driver-assist features like adaptive cruise control, forward-collision warning, automatic emergency braking, rear cross-traffic alert, blind-spot monitors, traffic-sign recognition, parking sensors, and lane-departure warning. Premium Plus and Prestige trims added a park-assist system, adaptive cruise assist, and a 360-degree camera system. The lane-centering feature allowed some lane wobble, but robust driver monitoring was included. Crash-test ratings were not available at the time of writing.