Compare the2025 Honda Civic SiVS 2025 Mazda 3

Using vehicle speed sensors and seat sensors, smart airbags in the Civic Si deploy with different levels of force or don’t deploy at all to help better protect passengers of all sizes in different collisions. The Civic Si’s side airbags will shut off if a child is leaning against the door. The Mazda 3’s side airbags don’t have smart features and will always deploy full force.

Both the Civic Si and the Mazda 3 have standard driver and passenger frontal airbags, front and rear side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, front and rear 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 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 Honda Civic Si is safer than the Mazda 3:

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, results indicate that the Honda Civic Si is safer than the Mazda 3:

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

There are almost 2 times as many Honda dealers as there are Mazda dealers, which makes it much easier should you ever need service under the Civic Si’s warranty.

J.D. Power and Associates’ 2024 Initial Quality Study of new car owners surveyed provide the statistics that show that Honda vehicles are better in initial quality than Mazda vehicles. J.D. Power ranks Honda above average in initial quality. With 51 more problems per 100 vehicles, Mazda is rated below average.

From surveys of all its subscribers, Consumer Reports’ January 2024 Auto Issue reports that Honda vehicles are more reliable than Mazda vehicles. Consumer Reports ranks Honda 2 places higher in reliability than Mazda.

The Civic Si’s 1.5 turbo 4-cylinder produces 9 more horsepower (200 vs. 191) and 6 lbs.-ft. more torque (192 vs. 186) than the Mazda 3’s standard 2.5 DOHC 4-cylinder.

As tested in Car and Driver the Honda Civic Si is faster than the Mazda 3 4 cyl. (manual transmissions tested):

On the EPA test cycle the Civic Si gets better mileage than the Mazda 3 Hatchback:

In heavy traffic or at stoplights the Civic Si’s engine automatically turns off when the vehicle is stopped, saving fuel and reducing pollution. The engine is automatically restarted when the driver gets ready to move again. If the conditions warrant or the driver wishes, the system can be manually disabled at any time for the duration of a trip. The Mazda 3 doesn’t offer an automatic engine start/stop system.

The Civic Si has a standard cap-less fueling system. The fuel filler is automatically opened when the fuel nozzle is inserted and automatically closed when it’s removed. This eliminates the need to unscrew and replace the cap and it reduces fuel evaporation, which causes pollution. The Mazda 3 doesn’t offer a cap-less fueling system.

For better stopping power the Civic Si’s brake rotors are larger than those on the Mazda 3:

The Civic Si stops much shorter than the Mazda 3:

For better traction, the Civic Si has larger tires than the Mazda 3 (235/40R18 vs. 205/60R16). The Civic Si’s tires are larger than the largest tires available on the Mazda 3 (235/40R18 vs. 215/45R18).

The Civic Si’s tires provide better handling because they have a lower 40 series profile (height to width ratio) that provides a stiffer sidewall than the Mazda 3 2.5 S Sedan’s standard 60 series tires. The Civic Si’s tires are lower profile than the Mazda 3 Select Sport/Preferred/Carbon/Premium’s 45 series tires.

For better ride, handling and brake cooling the Civic Si has standard 18-inch wheels. Smaller 16-inch wheels are standard on the Mazda 3 2.5 S Sedan.

For superior ride and handling, the Honda Civic Si has fully independent front and rear suspensions. An independent suspension allows the wheels to follow the road at the best angle for gripping the pavement, without compromising ride comfort. The Mazda 3 has a rear torsion beam axle, with a semi-independent rear suspension.

The Civic Si has standard front and rear stabilizer bars, which help keep the Civic Si flat and controlled during cornering. The Mazda 3’s suspension doesn’t offer a rear stabilizer bar.

The Civic Si has vehicle speed sensitive variable-assist power steering, for low-effort parking, better control at highway speeds and during hard cornering, and a better feel of the road. The Mazda 3 doesn’t offer variable-assist power steering.

The Civic Si handles at .97 G’s, while the Mazda 3 Carbon Edition Sedan AWD pulls only .83 G’s of cornering force in a Car and Driver skidpad test.

The Civic Si executes Motor Trend’s “Figure Eight” maneuver 1.8 seconds quicker than the Mazda 3 Carbon Edition Sedan AWD (26.3 seconds @ .67 average G’s vs. 28.1 seconds @ .58 average G’s).

Because it has more passenger and cargo room, the EPA rates the Civic Si a Mid-size car, while the Mazda 3 is rated a Compact.

The Civic Si has 3.8 cubic feet more passenger volume than the Mazda 3 Sedan (96.6 vs. 92.8).

The Civic Si has 1.3 inches more front shoulder room, 2.3 inches more rear legroom and 2.5 inches more rear shoulder room than the Mazda 3 Sedan.

The Civic Si has a larger trunk than the Mazda 3 Sedan (14.1 vs. 13.2 cubic feet).

The Civic Si’s standard Smart Entry allow you to unlock the doors from either front door handle, open the trunk, and start the engine, all without removing the key from the pocket or purse. Push Button Start standard on the Mazda 3 only offers hands-free access for the ignition, none to unlock the car. Push Button Start is not available on the Mazda 3 Select Sport/Preferred/Carbon/Premium.

The Civic Si’s speed-sensitive wipers speed up when the vehicle does, so that the driver doesn’t have to continually adjust the speed of the wipers. The Mazda 3 2.5 S’ standard manually variable intermittent wipers have to be constantly adjusted.

Consumer Reports rated the Civic Si’s headlight performance “Good,” a higher rating than the Mazda 3’s headlights, which were rated “Poor.”

The Civic Si’s standard outside mirrors include heating elements to clear off the mirrors for better visibility. Mazda only offers heated mirrors on the Mazda 3 Select Sport/Preferred/Carbon/Premium.

The Civic Si will cost the buyer less in the long run because of its superior resale value. The IntelliChoice estimates that the Civic Si will retain 60.14% of its original price after five years, while the Mazda 3 only retains 51.44% to 55.76%.

The Civic was chosen as a Car and Driver’s “Top Ten” for 2024 and 9 more times in the last 40 years. The Mazda 3 has never been chosen by Car and Driver in their “10Best” issue.

The Honda Civic outsold the Mazda 3 by almost seven to one during 2023.