2025 Audi S6 vs. 2026 BMW 8 Series

TrueCar says choosing between the Audi S6 and the BMW 8 Series comes down to price up front versus cost at the pump, with the S6's $77,195 starting price undercutting the 8 Series's $96,050 by $18,855, while the 8 Series wins on fuel economy at 21 city/29 highway mpg versus the S6's 19 city/27 highway mpg, and the S6's 2.9-liter twin-turbo V6 with AWD contrasts with the base 840i's 3.0-liter turbo inline-six with rear-wheel drive. Car and Driver rates the BMW 8-Series 8.5/10, saying it carries on the BMW grand-tourer legacy as a swift and elegant two-door with luxurious interior digs and plenty of poise, offering a velvety 335-hp inline-six in 840i models and a raucous 523-hp V8 in the all-wheel-drive M850i xDrive, sold as a hardtop coupe or softtop convertible, with the four-door 8-Series Gran Coupe reviewed separately.

Which to choose, and why

$18,855 cheaper, AWD standard

TrueCar (opens in a new tab) says choosing between the Audi S6 and the BMW 8 Series comes down to price up front versus cost at the pump, with the S6's $77,195 starting price undercutting the 8 Series's $96,050 by $18,855, and the S6's 2.9-liter twin-turbo V6 with AWD contrasts with the base 840i's 3.0-liter turbo inline-six with rear-wheel drive.

The 8-Series is thriftier

TrueCar (opens in a new tab) says the 8 Series wins on fuel economy at 21 city/29 highway mpg versus the S6's 19 city/27 highway mpg.

335 to 523 hp for the 8-Series grand tourer

Car and Driver (opens in a new tab) rates the BMW 8-Series 8.5/10, saying it carries on the BMW grand-tourer legacy as a swift and elegant two-door with luxurious interior digs and plenty of poise, offering a velvety 335-hp inline-six in 840i models and a raucous 523-hp V8 in the all-wheel-drive M850i xDrive, sold as a hardtop coupe or softtop convertible.

Questions buyers ask

How much horsepower does the BMW 8-Series have?

Car and Driver (opens in a new tab) says 335 hp in the 840i, up to 523 hp in the M850i xDrive.

Which is cheaper, the Audi S6 or BMW 8 Series?

TrueCar (opens in a new tab) says the S6, by $18,855 at MSRP.

Side-by-side matrix

The published fields that can change the decision.

Audi S6: 1 records · BMW 8 Series: 9 records.

Decision field	Audi S6	BMW 8 Series
Exact EPA records	1	9
Model / option labels	1	9
Drive layouts	All-Wheel Drive	All-Wheel Drive, Rear-Wheel Drive
Engines / propulsion	2.9L 6-cyl SIDI; Mild Hybrid	3L 6-cyl SIDI, 4.4L 8-cyl SIDI
Transmissions	Automatic (S8)	Automatic (S8)
Fuel types	Premium	Premium
EPA classes	Midsize Cars	Midsize Cars, Subcompact Cars
Combined efficiency	22 MPG/MPGe	19–24 MPG/MPGe
Electric range	Not listed	Not listed
Annual fuel / energy estimate	$3650 per year	$3300–4200 per year

Head to head

Audi S6 vs. BMW 8 Series: size, power, capability and price.

Measure	Audi S6	BMW 8 Series
Starting price (KBB base)	$77,195	$96,050
Top trim price (KBB base)	$85,395	$121,850
Horsepower	444 hp	335-523 hp
Torque	442 lb-ft	369-553 lb-ft
0 to 60 mph	4.4 sec	3.7-4.9 sec
Curb weight	4,486 lb	4,180-4,696 lb
Length	195 in	200.3 in
Wheelbase	115.3 in	119 in
Cargo volume	13.7 cu ft	15.5 cu ft
Seating	5 seats	5 seats
Basic warranty	4 years	4 years

Figures are ranges across each model’s trims from Kelley Blue Book records (2025 and 2026 model years); prices are KBB base prices.

The Audi S6 starts $18,855 lower: $77,195 against $96,050 before options and fees.
On peak horsepower, the BMW 8 Series leads: 523 hp against 444 hp.
On peak torque, the BMW 8 Series leads: 553 lb-ft against 442 lb-ft.
The BMW 8 Series is quicker to 60 mph: 3.7 sec against 4.4 sec.
The BMW 8 Series is lighter, comparing lightest trims: 4,180 lb against 4,486 lb.
On length, the BMW 8 Series leads: 200.3 in against 195 in.
On wheelbase, the BMW 8 Series leads: 119 in against 115.3 in.
On cargo volume, the BMW 8 Series leads: 15.5 cu ft against 13.7 cu ft.
Both list the same seating capacity: 5 seats.
Both list the same basic warranty: 4 years.

Background on each vehicle

What public sources say about the Audi S6 and the BMW 8 Series.

2025 Audi S6

The Audi S6 is a high-performance variant of the Audi A6, an executive car produced by German automaker Audi. It went on sale in 1994, shortly after the "A6" designation was introduced, replacing the "100" nameplate. The original S6 was largely identical to the outgoing Audi S4 (C4) (Often referred to as the Ur-S4), with the only visible differences being new body-cladding and badging.

Source: Audi S6 (Wikipedia)

Recent recalls (1 campaign across the latest model years)

December 2025, Back Over Prevention: Sensing System: Camera. Volkswagen Group of America, Inc. (Audi) is recalling certain 2019-2026 vehicles. Please see the recall report for a complete list of models. A software error may prevent the rearview camera image from displaying as intended. As such, these vehicles fail to comply… Consequence: A rearview image that does not display reduces the driver's view behind the vehicle, increasing the risk of a crash.

2026 BMW 8 Series

The BMW 8 Series is a range of grand tourer coupes and convertibles produced by BMW. The 8 Series was introduced in 1990 under the E31 model code and was only available as a two-door coupé. It is powered by a range of naturally aspirated V8 and V12 petrol engines.

Source: BMW 8 Series (Wikipedia)

Open both dossiers

Resolve the exact engine, drive and EPA ID.

01 · 2025Audi S61 configurations →02 · 2026BMW 8 Series9 configurations →

Comparison answer desk

13 answers for this exact pairing.

Q01Which is more efficient: the 2025 Audi S6 or the 2026 BMW 8 Series?

Efficiency

The 2025 Audi S6 lists the higher combined-efficiency midpoint in this snapshot (22 vs. the 2026 BMW 8 Series's 21.5 MPG/MPGe).