Compare the2024 Audi S4VS 2023 Mercedes AMG CLA

For enhanced safety, the front seat shoulder belts of the Audi S4 are height-adjustable to accommodate a wide variety of driver and passenger heights. A better fit can prevent injuries and the increased comfort also encourages passengers to buckle up. The Mercedes AMG CLA doesn’t offer height-adjustable seat belts.

Both the S4 and AMG CLA have child safety locks to prevent children from opening the rear doors. The S4 has power child safety locks, allowing the driver to activate and deactivate them from the driver's seat and to know when they're engaged. The AMG CLA’s child locks have to be individually engaged at each rear door with a manual switch. The driver can’t know the status of the locks without opening the doors and checking them.

The S4 has a standard Secondary Collision Brake Assist, which automatically applies the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The AMG CLA doesn’t offer a post collision braking system: in the event of a collision that triggers the airbags, more collisions are possible without the protection of airbags that may have already deployed.

The S4’s standard lane departure warning system alerts a temporarily inattentive driver when the vehicle begins to leave its lane and gently nudges the vehicle back towards its lane. A lane departure warning system costs extra on the AMG CLA.

Both the S4 and the AMG CLA have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, front and rear seatbelt pretensioners, four-wheel antilock brakes, all wheel drive, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, rearview cameras, available blind spot warning systems, around view monitors and rear cross-path warning.

The S4’s corrosion warranty is 7 years longer than the AMG CLA’s (12 vs. 5 years).

To reliably power the ignition and other systems and to recharge the battery, the S4 has a standard 150-amp alternator. The AMG CLA’s 115-amp alternator isn’t as powerful.

A reliable vehicle saves its owner time, money and trouble. Nobody wants to be stranded or have to be without a vehicle while it’s being repaired. Consumer Reports rates the S4’s reliability 19 points higher than the AMG CLA.

From surveys of all its subscribers, Consumer Reports’ January 2023 Auto Issue reports that Audi vehicles are more reliable than Mercedes vehicles. Consumer Reports ranks Audi 18 places higher in reliability than Mercedes.

The S4’s 3.0 turbo V6 produces 47 more horsepower (349 vs. 302) and 74 lbs.-ft. more torque (369 vs. 295) than the AMG CLA 35’s standard 2.0 turbo 4-cylinder. The S4’s 3.0 turbo V6 produces 15 lbs.-ft. more torque (369 vs. 354) than the AMG CLA 45’s standard 2.0 turbo 4-cylinder.

On the EPA test cycle the S4 gets better fuel mileage than the AMG CLA 45 (21 city/29 hwy vs. 20 city/28 hwy).

To lower fuel costs and make buying fuel easier, the Audi S4 uses regular unleaded gasoline (premium recommended for maximum performance). The AMG CLA requires premium, which can cost on average about 82.8 cents more per gallon.

The S4 has 1.8 gallons more fuel capacity than the AMG CLA (15.3 vs. 13.5 gallons), for longer range between fill-ups.

In its Green Vehicle Guide, the U.S. Environmental Protection Agency (EPA) rates the Audi S4 higher (5 out of 10) than the Mercedes AMG CLA (3 to 5). This means the S4 produces up to 16.5 pounds less smog-producing pollutants than the AMG CLA every 15,000 miles.

For better traction, the S4 has larger tires than the AMG CLA (255/35R19 vs. 235/40R18).

The S4’s tires provide better handling because they have a lower 35 series profile (height to width ratio) that provides a stiffer sidewall than the AMG CLA 35’s standard 40 series tires.

For better ride, handling and brake cooling the S4 has standard 19-inch wheels. Smaller 18-inch wheels are standard on the AMG CLA 35.

The S4 has a standard space-saver spare tire so you can replace a flat tire and drive to have the flat repaired or replaced. A spare tire isn’t available on the AMG CLA; it requires you to depend on its run-flat tires, which limits mileage and speed before they are repaired. If a run-flat is damaged beyond repair by a road hazard your vehicle will have to be towed. Some tire options on the AMG CLA don’t have a run-flat feature, either.

For a smoother ride and more stable handling, the S4’s wheelbase is 3.6 inches longer than on the AMG CLA (111 inches vs. 107.4 inches).

The S4’s front to rear weight distribution is more even (57% to 43%) than the AMG CLA’s (60% to 40%). This gives the S4 more stable handling and braking.

The S4 has 3 cubic feet more passenger volume than the AMG CLA (92 vs. 89).

The S4 has .8 inches more front shoulder room, 1.7 inches more rear headroom, 1.8 inches more rear legroom and .5 inches more rear shoulder room than the AMG CLA.

The S4 has a larger trunk than the AMG CLA (12 vs. 11.6 cubic feet).

With its sedan body style, valet key, locking rear seatbacks and remote trunk release lockout, the S4 offers cargo security. The AMG CLA’s non-lockable remote release defeats cargo security.

The engine in the S4 is mounted longitudinally (North-South), instead of sideways, as in the AMG CLA. This makes it easier to service and maintain, because the accessory belts are in front.

J.D. Power and Associates surveys of service recipients show that Audi service is better than Mercedes. J.D. Power ranks Audi 8th in service department satisfaction (above the industry average). With a 16% lower rating, Mercedes is ranked 18th.

In poor weather, headlights can lose their effectiveness as grime builds up on their lenses. This can reduce visibility without the driver realizing. The S4 Prestige has standard headlight washers to keep headlight output high. The AMG CLA doesn’t offer headlight washers.

To shield the driver and front passenger’s vision over a larger portion of the windshield and side windows, the S4 has standard extendable sun visors. The AMG CLA doesn’t offer extendable visors.

Manual rear side window sunshades are available in the S4 to help block heat and glare for the rear passengers. The AMG CLA doesn’t offer rear side window sunshades.

The S4 has standard heated front seats. Heated front seats cost extra on the AMG CLA. The S4 Prestige also has standard heated rear seats to keep those passengers extremely comfortable in the winter. Heated rear seats aren’t available in the AMG CLA.

On extremely cold winter days, the S4’s standard heated steering wheel provides comfort, allowing the driver to steer safely and comfortably before the car heater warms up. The AMG CLA doesn’t offer a heated steering wheel.

The Audi A4/S4 outsold the Mercedes CLA by 74% during 2022.