Compare the2024 BMW Z4VS 2023 Audi S5

The Z4’s driver alert monitor detects an inattentive driver then sounds a warning and suggests a break. According to the NHTSA, drivers who fall asleep cause about 100,000 crashes and 1500 deaths a year. The S5 doesn’t offer a driver alert monitor.

Both the Z4 and the S5 have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger knee airbags, front seatbelt pretensioners, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, post-collision automatic braking systems, daytime running lights, rearview cameras, available lane departure warning systems, blind spot warning systems, rear parking sensors and rear cross-path warning.

BMW pays for scheduled maintenance on the Z4 for 3 years and 36,000 miles. BMW will pay for oil changes, air filter replacements, cabin filter replacement, brake fluid replacement, inspections, and any other required maintenance. Audi only pays for the first scheduled maintenance visit on the S5.

There are over 15 percent more BMW dealers than there are Audi dealers, which makes it easier should you ever need service under the Z4’s warranty.

To reliably power the ignition and other systems and to recharge the battery, the Z4 has a standard 170-amp alternator. The S5’s 150-amp alternator isn’t as powerful.

To reliably start during all conditions and help handle large electrical loads, the Z4 has a standard 800-amp battery. The S5’s 420-amp battery isn’t as powerful.

J.D. Power and Associates’ 2023 Initial Quality Study of new car owners surveyed provide the statistics that show that BMW vehicles are better in initial quality than Audi vehicles. With 29 fewer problems per 100 vehicles, JD Power ranks BMW higher than Audi.

J.D. Power and Associates’ 2022 survey of the owners of three-year-old vehicles provides the long-term dependability statistics that show that BMW vehicles are more reliable than Audi vehicles. J.D. Power ranks BMW above average in long-term dependability. With 5 more problems per 100 vehicles in the first three years of ownership, Audi is rated below average.

From surveys of all its subscribers, Consumer Reports’ January 2023 Auto Issue reports that BMW vehicles are more reliable than Audi vehicles. Consumer Reports ranks BMW third in overall reliability. Audi is ranked 6th.

The Z4 M40i’s standard 3.0 turbo 6-cylinder produces 33 more horsepower (382 vs. 349) than the S5’s 3.0 turbo V6.

As tested in Car and Driver the Z4 M40i 3.0 turbo 6-cylinder is faster than the Audi S5:

On the EPA test cycle the Z4 gets better mileage than the S5 Cabriolet:

The Z4’s launch control uses engine electronics to hold engine RPM’s precisely in order to provide the most stable and rapid acceleration possible, using all of the available traction. The S5 doesn’t offer launch control.

The Z4 stops shorter than the S5:

For better handling and stability, the average track (width between the wheels) on the Z4 is .8 inches wider in the front and 1.3 inches wider in the rear than the track on the S5.

The Z4’s front to rear weight distribution is more even (51.2% to 48.8%) than the S5’s (56.7% to 43.3%). This gives the Z4 more stable handling and braking.

For better maneuverability, the Z4’s turning circle is 1.6 feet tighter than the S5’s (36.1 feet vs. 37.7 feet).

The BMW Z4 may be more efficient, handle and accelerate better because it weighs about 550 to 700 pounds less than the Audi S5.

The Z4 is 1 foot, 2.2 inches shorter than the S5, making the Z4 easier to handle, maneuver and park in tight spaces.

The design of the BMW Z4 amounts to more than styling. The Z4 offers aerodynamic coefficients of drag from .29 to .31 Cd (depending on bodystyle and options). That is lower than the S5 (.31 to .32) and many sports cars. A more efficient exterior helps keep the interior quieter and helps the Z4 get better fuel mileage.

The Z4 has a much larger trunk with its top down than the S5 Cabriolet with its top down (9.9 vs. 7.3 cubic feet). The Z4 has a larger trunk than the S5 Cabriolet with its top up (9.9 vs. 9.3 cubic feet).

J.D. Power and Associates surveys of service recipients show that BMW service is better than Audi. J.D. Power ranks BMW 7th in service department satisfaction (above the industry average). With a 1% lower rating, Audi is ranked 8th.

The Z4 offers a remote vehicle starting system, so the vehicle can be started from inside the driver's house. This allows the driver to comfortably warm up the engine before going out to the vehicle. The climate system will also automatically heat or cool the interior. The S5 doesn’t offer a remote starting system.

Unlike the driver-only memory system optional at extra cost in the S5, the Z4 has standard driver and passenger memory, so that when drivers switch, the memory setting adjusts the driver’s seat, outside mirror angle, climate settings and radio stations and the front passenger seat also adjusts to the new passenger’s preset preferences.

In case of a sudden change of weather, the Z4 offers an optional remote convertible top that can be raised from a distance to protect the interior of the vehicle from damage. On a hot day the Z4 offers an optional remote opening feature, to lower the top from outside. The S5 doesn’t offer a remote top, so the driver will have to run to the car, get in, turn the ignition on and raise the top to prevent the interior from being damaged.

The Z4’s power window, power lock, power mirror and cruise control switches are lit from behind, making them plainly visible and easier to operate at night. The S5’s cruise control switches are unlit, making them difficult to find at night and operate safely.

Insurance will cost less for the Z4 owner. The Complete Car Cost Guide estimates that insurance for the Z4 will cost $2915 to $5530 less than the S5 over a five-year period.

IntelliChoice estimates that five-year ownership costs (depreciation, financing, insurance, fuel, fees, repairs and maintenance) for the BMW Z4 will be $7666 to $7704 less than for the Audi S5.

Consumer Reports® recommends the BMW Z4, based on reliability, safety and performance.