2026 Audi RS Q8 vs 2026 Mercedes-Benz GLS

$138,300 · Crossover

$90,250 · Crossover

Comparison Overview

The most significant numerical divergence between the 2026 Audi RS Q8 (car1) and the 2026 Mercedes-Benz GLS (car2) is the $48,050 MSRP gap, listing the Audi at $138,300 versus the Mercedes' $90,250. Performance metrics heavily favor the RS Q8, which outputs 631 hp and 627 lb-ft of torque compared to the GLS's 375 hp and 369 lb-ft of torque, a substantial 256 hp deficit for car2. This power comes at the expense of efficiency; the RS Q8 achieves only 16 combined MPG, while the GLS delivers 21 combined MPG, resulting in a 5 MPG difference. In terms of size, the GLS is longer at 205.0 inches and taller at 71.8 inches. However, the Audi boasts significantly more cargo space at 33 cubic feet versus the GLS's 17.4 cubic feet, despite the GLS being the physically larger vehicle overall.

Size Comparison

Performance

Fuel Efficiency

Full Specifications

Our Verdicts

🚗 Best for Commuters

2026 Mercedes-Benz GLS

The Mercedes-Benz GLS is the superior commuter due to its superior fuel economy of 21 combined MPG versus the Audi's 16 combined MPG.

👨‍👩‍👧‍👦 Best for Families

2026 Audi RS Q8

Despite its higher price, the Audi RS Q8 offers superior utility with 33 cubic feet of cargo capacity compared to the GLS's 17.4 cubic feet.

🏎️ Best for Enthusiasts

2026 Audi RS Q8

The Audi RS Q8 dominates performance metrics, delivering 631 horsepower and 627 lb-ft of torque.

💰 Best Value

2026 Mercedes-Benz GLS

The Mercedes-Benz GLS provides substantially less power for $48,050 less, making its 375 hp highly economical compared to the RS Q8's cost per horsepower.

Choose the Audi RS Q8 if...

Maximum straight-line performance (631 hp and 627 lb-ft torque) is the absolute priority.
A premium, performance-oriented badge presence justifying the $138,300 MSRP is desired.
Superior cargo volume of 33 cubic feet is required within the performance crossover segment.

Choose the Mercedes-Benz GLS if...

Fuel cost savings are crucial, given the 21 combined MPG versus the Audi's 16 combined MPG.
Budgetary constraints favor the significantly lower starting MSRP of $90,250.
A smoother, perhaps more comfortable ride is expected, aided by the GLS's larger overall dimensions (205.0 inches long, 71.8 inches high).

Key Dimensions

Dimension	Audi RS Q8	Mercedes-Benz GLS
Length	197.7"	205.0"
Width	79.0"	79.9"
Height	67.5"	71.8"
Wheelbase	117.9"	123.4"

Features Comparison

Safety

Feature	Audi	Mercedes-Benz
Blind Spot Monitor	✓	✓
Lane Departure Warning	✓	✓
Lane Keeping Assist System	✓	✓
Rear Cross Traffic Alert	✓	✓
Pre-Collision Safety System	✓	✓
Post-Collision Safety System	✓	✓
Dual Front Side-Mounted Airbags	✓	✓
Dual Rear Side-Mounted Airbags	✓	—
Front Head Airbags	✓	✓
Rear Head Airbags	✓	✓
Passenger Airbag Occupant Sensing Deactivation	✓	✓
Electronic Stability Control	✓	✓
Traction Control System	✓	✓
LATCH System	✓	✓
Rear Door Child Safety Locks	✓	✓
Anti-lock Brakes (ABS)	4-Wheel	4-Wheel
Brake Assist	✓	✓
Tire Pressure Monitoring System	✓	✓
Automatic Headlights	✓	✓
Headlight Delay-Off	✓	✓
LED Headlights	✓	✓
Daytime Running Lights	✓	✓
Integrated Turn Signal Mirrors	✓	✓
Front Headrests	2	2
Front Integrated Headrests	✓	—
Rear Headrests	3	3
Rear Height Adjustable Headrests	✓	✓
Rear Center 3-Point Seatbelt	✓	✓
Anti-Theft Alarm System (Remote)	✓	✓
Engine Immobilizer	✓	✓
Front Cross Traffic Alert	—	✓
Driver Attention Alert	—	✓
Third Row Head Airbags	—	✓
Brake Drying	—	✓
Front Ventilated Disc Brakes	—	✓
Rear Ventilated Disc Brakes	—	✓
Brake Preparation System	—	✓
Adaptive Headlights	—	✓
Cornering Lights	—	✓
Front Power Adjustable Headrests	—	✓

Engine

Feature	Audi	Mercedes-Benz
Base Engine Displacement	4.0 L	3.0 L
Number of Cylinders	V8	inline 6
Base Engine Type	mild hybrid	mild hybrid
Horsepower	631 hp @ 6000 rpm	375 hp @ 5800 rpm
Torque	627 lb-ft @ 2300 rpm	369 lb-ft @ 1800 rpm
Number of Valves	32	24
Camshaft Type	Double overhead cam (DOHC)	Double overhead cam (DOHC)
Variable Valve Timing	Variable	Variable
Fuel Injection Type	✓	✓

Drive Train

Feature	Audi	Mercedes-Benz
Transmission Type	8-speed shiftable automatic	9-speed shiftable automatic
Drivetrain Type	all wheel drive	all wheel drive
[object Object]	✓	—
[object Object]	✓	—
Hill Descent Control	✓	✓
Center Differential Type	—	Limited Slip

Fuel

Feature	Audi	Mercedes-Benz
Fuel Type	premium unleaded (required)	premium unleaded (required)
EPA Fuel Economy (City/Highway)	14/20 MPG	19/24 MPG
EPA Fuel Economy (Combined)	16 MPG	21 MPG
EPA Driving Range (City/Highway)	315.0/450.0 mi.	452.2/571.2 mi.
Fuel Tank Capacity	22.5 gal.	23.8 gal.

Comfort & Convenience

Feature	Audi	Mercedes-Benz
Push Button Start	✓	✓
Power Tilt and Telescopic Steering Wheel	✓	✓
Transmission Controls on Steering Wheel	✓	✓
Audio Controls on Steering Wheel	✓	✓
Electric Power Steering	✓	✓
Front View Camera	✓	✓
Side View Camera	✓	✓
Rear View Camera	✓	✓
Front Parking Sensors	✓	✓
Rear Parking Sensors with Side Sensing	✓	—
Wireless Charging Pad	✓	✓
Adaptive Cruise Control	✓	✓
Universal Remote Transmitter	✓	✓
Front Cupholders	✓	✓
Rear Cupholders	✓	✓
Front Door Pockets	✓	✓
Rear Door Pockets	✓	✓
Front Seatback Storage	✓	✓
Leather Steering Wheel	✓	✓
Heated Steering Wheel	✓	—
Four Zone Climate Control	✓	✓
Rear Ventilation Ducts with Fan Control	✓	✓
Interior Air Filtration	✓	✓
Dual Vanity Mirrors	✓	✓
Auto-Dimming Rearview Mirror	✓	✓
Turn Signal Indicators in Mirrors	✓	✓
Cruise Control on Steering Wheel	—	✓
Rear Parking Sensors	—	✓
Automatic Parking Assist	—	✓
3rd Row Cupholders	—	✓
Overhead Console with Storage	—	✓
Power Rear Seat Easy Entry	—	✓

In Car Entertainment

Feature	Audi	Mercedes-Benz
Infotainment Display	10.1 in	12.3 in
AM/FM Stereo	✓	✓
Premium Brand Speakers	Bang & Olufsen	—
Stereo Power	730W	590W
Speaker System	17	13
Subwoofer Count	1	2
Surround Audio	Discrete	Discrete
Android Auto (Wireless)	✓	✓
Apple CarPlay (Wireless)	✓	✓
USB Port	✓	✓
USB Port with External Media Control	✓	✓
Satellite Radio	✓	✓
Satellite Radio Trial Period	3 months	6 months
Premium Speaker Brand	—	Burmester
Speed Sensitive Volume Control	—	✓

Power Feature

Feature	Audi	Mercedes-Benz
One-Touch Power Windows	4	4
Moonroof Type	1st Row Power Glass Extended	1st Row Power Glass Extended
Keyless Entry	✓	✓
Heated Mirrors	✓	✓
Reverse Tilt Passenger Mirror	—	✓

Frontseats

Feature	Audi	Mercedes-Benz
Front Head Room	37.1 in.	39.4 in.
Front Leg Room	41.3 in.	40.3 in.
Front Shoulder Room	59.5 in.	59.3 in.
Seat Material: Premium Leather	✓	—
Front Seat Type: Sport	✓	—
Driver Seat Power Adjustments	8-way	10-way
Driver Seat Height Adjustment	✓	✓
Driver Seat Lumbar Support	Power	Power
Driver Seat Memory Settings	2	3
Passenger Seat Power Adjustments	8-way	10-way
Passenger Seat Height Adjustment	✓	✓
Passenger Seat Lumbar Support	Power	Power
Passenger Seat Memory Settings	2	3
Driver Seat Heating	Multi-level	Multi-level
Passenger Seat Heating	Multi-level	Multi-level
Driver Seat Ventilation	✓	✓
Passenger Seat Ventilation	✓	✓
Front Hip Room	—	60.8 in.
Seat Material: Leatherette	—	✓
Front Seat Type: Bucket	—	✓
Driver Seat Thigh Extension	—	✓
Passenger Seat Thigh Extension	—	✓

Rearseats

Feature	Audi	Mercedes-Benz
Rear Head Room	38.1 in.	40.2 in.
Rear Leg Room	40.2 in.	41.9 in.
Rear Shoulder Room	58.4 in.	58.5 in.
Split-Folding Rear Seatback	✓	✓
Reclining Rear Seats	✓	✓
Folding Center Armrest	✓	✓
Rear Hip Room	—	60.0 in.
Power Folding Third Row Seat	—	✓

Tires and Wheels

Feature	Audi	Mercedes-Benz
Wheel Material	Alloy	Alloy
Wheel Diameter	22 in	—
Tire Type	Performance	All Season
Tire Size	295/40R22	315/40R21
Wheel Size	—	21 x 11.0 in.
Spare Tire Type	—	Temporary
Spare Tire Location	—	Inside Mounted

Suspension

Feature	Audi	Mercedes-Benz
Four-Wheel Independent Suspension	✓	✓
Front Stabilizer Bar	✓	✓
Rear Stabilizer Bar	✓	✓

Warranty

Feature	Audi	Mercedes-Benz
Basic Warranty	4 yr./ 50000 mi.	4 yr./ 50000 mi.
Drivetrain Warranty	4 yr./ 50000 mi.	4 yr./ 50000 mi.
Corrosion/Rust Warranty	12 yr./ unlimited mi.	4 yr./ 50000 mi.
Roadside Assistance	4 yr./ unlimited mi.	4 yr./ 50000 mi.
Complimentary Scheduled Maintenance	3 yr./ 30000 mi.	—
Hybrid Component Warranty	—	6 yr./ 62000 mi.

Frequently Asked Questions

Common questions about comparing the 2026 Audi RS Q8 and 2026 Mercedes-Benz GLS.

What is the exact horsepower difference between the 2026 Audi RS Q8 and the 2026 Mercedes-Benz GLS?

The Audi RS Q8 significantly outperforms the GLS in power output, delivering 631 hp compared to the Mercedes-Benz GLS's 375 hp. This results in a substantial 256 hp advantage for the Audi.

How does the fuel economy compare for daily driving between these two luxury crossovers?

The Mercedes-Benz GLS offers better everyday efficiency with 21 combined MPG (19 city/24 highway). The Audi RS Q8 is significantly thirstier, rated only at 16 combined MPG (14 city/20 highway).

Which vehicle offers better utility based on their listed cargo specifications?

Despite being the physically smaller vehicle in overall length and height, the Audi RS Q8 offers nearly double the utility with 33 cubic feet of cargo space compared to the GLS's 17.4 cubic feet.

What is the price separation between the 2026 Audi RS Q8 and the 2026 Mercedes-Benz GLS?

There is a $48,050 difference in their Manufacturer's Suggested Retail Prices. The Audi RS Q8 starts at $138,300, whereas the Mercedes-Benz GLS is listed at $90,250.

Are the transmissions different between the two high-performance SUVs?

Yes, the transmission specifications differ; the Audi RS Q8 utilizes an 8-speed shiftable automatic, while the Mercedes-Benz GLS is equipped with a 9-speed shiftable automatic transmission.