The Mazda6 has standard Whiplash Reducing Headrests, which use a specially designed headrest to protect the driver and front passenger from whiplash. During a rear-end collision, the Whiplash Reducing Headrests system moves the headrests forward to prevent neck and spine injuries. The Fusion doesn't offer a whiplash protection system.

Over 200 people are killed each year when backed over by motor vehicles. The Mazda6 Signature has standard Smart Brake Support that uses rear sensors to monitor and automatically apply the brakes to prevent a rear collision. The Fusion doesn't offer backup collision prevention brakes.

The Mazda6 Signature has a standard 360-degree View Monitor to allow the driver to see objects all around the vehicle on a screen. The Fusion only offers a rear monitor and rear parking sensors that beep or flash a light. That doesn't help with obstacles to the front or sides.

Both the Mazda6 and the Fusion have standard driver and passenger frontal airbags, front side-impact airbags, side-impact head airbags, front seatbelt pretensioners, front wheel drive, height adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, lane departure warning systems, blind spot warning systems, rearview cameras, rear cross-path warning and available driver alert monitors.

The National Highway Traffic Safety Administration does 35 MPH front crash tests on new vehicles. In this test, results indicate that the Mazda6 is safer than the Ford Fusion:

New test not comparable to pre-2011 test results. More stars = Better. Lower test results = Better.

The National Highway Traffic Safety Administration does side impact tests on new vehicles. In this test, which crashes the vehicle into a flat barrier at 38.5 MPH and into a post at 20 MPH, results indicate that the Mazda6 is safer than the Ford Fusion:

New test not comparable to pre-2011 test results. More stars = Better. Lower test results = Better.

For its top level performance in IIHS driver and passenger-side small overlap frontal, moderate overlap frontal, side impact, roof strength and head restraint tests, its standard vehicle-to-vehicle front crash prevention system, its standard vehicle-to-pedestrian front crash prevention system, and its standard headlight's “Good” rating, the Insurance Institute for Highway Safety grants the Mazda6 its highest rating: “Top Pick Plus” for 2021, a rating granted to only 35 vehicles tested by the IIHS. The Fusion last would have qualified as only a standard “Top Pick” in 2017.

A hardened steel chain, with no maintenance needs, drives the camshafts in the Mazda6's engine. A rubber cam drive belt that needs periodic replacement drives the Fusion's camshafts. If the Fusion's belt breaks, the engine could be severely damaged when the pistons hit the opened valves.

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 Mazda6's reliability 27 points higher than the Fusion.

From surveys of all its subscribers, Consumer Reports' December 2019 Auto Issue reports that Mazda vehicles are more reliable than Ford vehicles. Consumer Reports ranks Mazda second in reliability. Ford is ranked 16th.

The Mazda6 has more powerful engines than the Fusion:

As tested in Road and Track the Mazda6 4 cyl. is faster than the Fusion S 2.5 DOHC 4-cylinder:

On the EPA test cycle the Mazda6 with its standard engine gets better fuel mileage than the Fusion S FWD (26 city/35 hwy vs. 21 city/31 hwy).

An engine control system that can shut down some of the engine's cylinders helps improve the Mazda6 (except Turbo)'s fuel efficiency. The Fusion doesn't offer a system that can shut down part of the engine.

For better stopping power the Mazda6 Turbo's front brake rotors are larger than those on the Fusion:

The Mazda6 stops shorter than the Fusion:

For better traction, the Mazda6 has larger tires than the Fusion (225/55R17 vs. 215/60R16).

The Mazda6 Sport's standard tires provide better handling because they have a lower 55 series profile (height to width ratio) that provides a stiffer sidewall than the Fusion S' standard 60 series tires.

For better ride, handling and brake cooling the Mazda6 Sport has standard 17-inch wheels. Smaller 16-inch wheels are standard on the Fusion S.

The Mazda6 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 Fusion; it requires you to depend on roadside assistance and your vehicle will have to be towed.

For better maneuverability, the Mazda6's turning circle is .8 feet tighter than the Fusion's (36.7 feet vs. 37.5 feet).

The Mazda6 (except Sport) offers available computer-generated active noise cancellation to help remove annoying noise and vibration from the passenger compartment, especially at low frequencies. The Fusion doesn't offer active noise cancellation.

The Mazda6 Grand Touring Reserve/Signature/Carbon Edition has a standard heads-up display that projects speed and other key instrumentation readouts in front of the driver's line of sight, allowing drivers to view information without diverting their eyes from the road. The Fusion doesn't offer a heads-up display.

The Insurance Institute for Highway Safety (IIHS) conducts detailed tests on headlights for their range both straight ahead and in curves and to be certain they don't exceed acceptable amounts of glare to oncoming drivers. The Mazda6's headlights were rated “Good” to “Acceptable” by the IIHS, while the Fusion's headlights are rated “Poor.”

To help drivers see further while navigating curves, the Mazda6 Grand Touring Reserve/Signature/Carbon Edition has standard adaptive headlights to illuminate around corners automatically by reading vehicle speed and steering wheel angle. The Fusion doesn't offer cornering lights.

Both the Mazda6 and the Fusion offer available heated front seats. The Mazda6 Grand Touring Reserve/Signature/Carbon Edition also has standard heated rear seats to keep those passengers extremely comfortable in the winter. Heated rear seats aren't available in the Fusion.

The Mazda6 has a standard dual zone air conditioning allows the driver and front passenger to choose two completely different temperatures so people with different temperature preferences won't have to compromise. This makes both the driver and front passenger as comfortable as possible. Dual zone air conditioning costs extra on the Fusion.

Insurance will cost less for the Mazda6 owner. The Complete Car Cost Guide estimates that insurance for the Mazda6 will cost $265 less than the Fusion over a five-year period.

The Mazda6 will cost the buyer less in the long run because of its superior resale value. The IntelliChoice estimates that the Mazda6 will retain 45.59% to 48.35% of its original price after five years, while the Fusion only retains 39.71% to 43.24%.

According to The Car Book by Jack Gillis, the Mazda6 is less expensive to operate than the Fusion because typical repairs cost much less on the Mazda6 than the Fusion, including $220 less for a muffler, $86 less for front brake pads, $22 less for a starter, $92 less for a timing belt/chain and $237 less for a power steering pump.

IntelliChoice estimates that five-year ownership costs (depreciation, financing, insurance, fuel, fees, repairs and maintenance) for the Mazda6 will be $1308 to $5277 less than for the Ford Fusion.

Consumer Reports® recommends both the Mazda6 and the Ford Fusion, based on reliability, safety and performance.

The Mazda6 was chosen as one of Car and Driver's “Top Ten” for 2 of the last 7 years. The Fusion Hybrid hasn't been picked since 2010.