Compare the2026 Honda Civic SiVS 2025 Kia K4

Safety
Warranty
Reliability
Engine
Fuel Economy and Range
Transmission
Brakes and Stopping
Tires and Wheels
Suspension and Handling
Passenger Space
Cargo Capacity
Servicing Ease
Ergonomics
Recommendations

Safety

© 1999 - 2025Advanta-STAR Automotive Research, all rights reserved. This vehicle comparison and all of the content in it are provided only by license from Advanta-STAR Automotive Research Corporation of America (“Advanta-STAR”). If you are not a legally licensed user of this vehicle comparison, it is against federal law to access it, copy it, forward it, or use it in any manner whatsoever. Any unauthorized use of this vehicle comparison is a violation of U.S. and international law and is punishable criminally and civilly. Removal of this watermark/notification without prior written license and approval received from Advanta-STAR is an agreement, understanding, and/or stipulation by the person(s), entities, agents, attorneys, and any other persons involved in the removal of this watermark/notification (including but not limited to Search Optics, LLC and any and all parent entities, sister entities, and subsidiary entities of Search Optics, LLC and/or any other entity, agent, attorney, and persons related in any manner to Search Optics, LLC) to: 1) an agreed upon amount of liquidated monetary damages of a minimum of $1,250,000.00 US Dollars in favor of Advanta-STAR; 2) the jurisdiction and enforcement of any legal claims associated with this matter asserted by Advanta-STAR in the United States Federal District Court in Portand, Oregon; and 3) service of process of any legal claims asserted by Advanta-STAR associated with this matter may be accomplished by First-Class Postage by the United States Postal Service or comparable service. KTTKE-57BRP 2a06:98c0:3600::103 2025/07/17

The Honda Civic Si has standard driver and front passenger side knee airbags mounted low on the dashboard. These airbags help prevent the driver and front passenger from sliding under their seatbelts or the main frontal airbags; this keeps them better positioned during a collision for maximum protection. Knee airbags also help keep the legs from striking the dashboard, preventing knee and leg injuries in the case of a serious frontal collision. The K4 doesn’t offer knee airbags.

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 K4’s side airbags don’t have smart features and will always deploy full force.

The Civic Si’s 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. The K4 doesn’t offer a lane departure warning system.

The Civic Si has a standard blind spot warning system that uses sensors to alert the driver to objects in the vehicle’s blind spots where the side view mirrors don’t reveal them. A system to reveal vehicles in the K4’s blind spot costs extra.

To help make backing out of a parking space safer, the Civic Si has standard Rear Cross Traffic Monitor, helping the driver avoid collisions. Only the K4 LXS/EX/GT-Line offers Rear Cross-Traffic Collision Warning.

Both the Civic Si and the K4 have standard driver and passenger frontal airbags, front and rear side-impact 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, rearview cameras 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 Kia K4:

	Civic Si	K4
	Driver
STARS	5 Stars	5 Stars
HIC	325	375
Neck Compression	23 lbs.	39 lbs.
	Passenger
STARS	4 Stars	4 Stars
Chest Compression	.4 inches	.7 inches
Neck Injury Risk	25%	30.2%
Neck Compression	61 lbs.	70 lbs.

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 Kia K4:

	Civic Si	K4
	Front Seat
STARS	5 Stars	5 Stars
HIC	195	222
Chest Movement	.7 inches	1 inches
Hip Force	286 lbs.	361 lbs.
	Rear Seat
STARS	5 Stars	5 Stars
HIC	268	320
Hip Force	516 lbs.	678 lbs.

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

Side impacts caused 23% of all road fatalities in 2018, down from 29% in 2003, when the Insurance Institute for Highway Safety introduced its side barrier test. In order to continue improving vehicle safety, the IIHS has started using a more severe side impact test: 37 MPH (up from 31 MPH), with a 4180-pound barrier (up from 3300 pounds). The results of this newly developed test demonstrates that the Honda Civic Si is safer than the K4:

	Civic Si	K4
Overall Evaluation	GOOD	GOOD
Structure	GOOD	ACCEPTABLE
	Driver Injury Measures
Head/Neck	GOOD	GOOD
Head Injury Criterion	238	253
Neck Tension	178 lbs.	335 lbs.
Torso	ACCEPTABLE	ACCEPTABLE
Torso Max Deflection	1.38 in	1.57 in
Torso Deflection Rate	8 MPH	9 MPH
Pelvis	ACCEPTABLE	ACCEPTABLE
Head Protection	GOOD	GOOD
	Passenger Injury Measures
Head/Neck	GOOD	GOOD
Torso	GOOD	ACCEPTABLE
Shoulder Deflection	1.46 in	2.01 in
Torso Max Deflection	1.26 in	1.34 in
Torso Deflection Rate	5 MPH	9 MPH
Pelvis	GOOD	GOOD
Head Protection	GOOD	GOOD

Warranty

The Civic Si’s 5 year corrosion warranty has no mileage limitations, but the corrosion warranty on the K4 runs out after 100,000 miles.

There are over 34 percent more Honda dealers than there are Kia dealers, which makes it easier should you ever need service under the Civic Si’s warranty.

Reliability

From surveys of all its subscribers, Consumer Reports’ March 2025 Auto Issue reports that Honda vehicles are more reliable than Kia vehicles. Consumer Reports ranks Honda fourth in overall reliability. Kia is ranked 9th.

Engine

The Civic Si’s 1.5 turbo 4-cylinder produces 53 more horsepower (200 vs. 147) and 60 lbs.-ft. more torque (192 vs. 132) than the K4’s standard 2.0 DOHC 4-cylinder. The Civic Si’s 1.5 turbo 4-cylinder produces 10 more horsepower (200 vs. 190) than the K4 GT-Line Turbo’s standard 1.6 turbo 4-cylinder.

Fuel Economy and Range

On the EPA test cycle the Civic Si gets better fuel mileage than the K4 GT-Line Turbo 1.6 turbo 4-cylinder 8-speed Auto (27 city/37 hwy vs. 26 city/36 hwy).

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 K4 doesn’t offer a cap-less fueling system.

Transmission

The Civic Si offers a manual transmission for better acceleration, control and sportiness. The K4 doesn’t offer a manual transmission.

Brakes and Stopping

For better stopping power the Civic Si’s brake rotors are larger than those on the K4:

	Civic Si	K4	K4 GT-Line Turbo
Front Rotors	12.3 inches	11 inches	12 inches
Rear Rotors	11.1 inches	10 inches	11.2 inches

The Civic Si stops much shorter than the K4:

	Civic Si	K4
70 to 0 MPH	156 feet	173 feet	Car and Driver
60 to 0 MPH	102 feet	121 feet	Motor Trend

Tires and Wheels

For better traction, the Civic Si has larger tires than the K4 (235/40R18 vs. 205/55R16).

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 K4 LX/LXS’ standard 55 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 K4 LX/LXS.

Suspension and Handling

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 K4 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 K4 base model’s suspension doesn’t offer a rear stabilizer bar.

The Civic Si handles at .97 G’s, while the K4 GT-Line Turbo 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 1.9 seconds quicker than the K4 GT-Line (26.1 seconds vs. 28 seconds).

Passenger Space

The Civic Si has 1 inch more front hip room, .5 inches more front shoulder room and 1.3 inches more rear shoulder room than the K4.

Cargo Capacity

The Civic Si’s standard folding rear seats are split to accommodate bulky cargo. The K4’s standard single piece folding rear seat is not as flexible; long cargo and a passenger can’t share the rear seat.

Servicing Ease

J.D. Power and Associates surveys of service recipients show that Honda service is better than Kia. J.D. Power ranks Honda 7th in service department satisfaction (above the industry average). With a 41% lower rating, Kia is ranked 27th.

Ergonomics

The Civic Si’s front power windows open or close fully with one touch of the switches, making it more convenient at drive-up windows and toll booths, or when talking with someone outside the car. The K4’s standard passenger windows don’t open or close automatically. The K4 EX/GT-Line’s rear windows don’t close automatically.

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 K4’s manually variable intermittent wipers have to be constantly adjusted.

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 Civic Si’s headlights were rated “Good” by the IIHS, while the K4’s headlights are rated “Acceptable.”

Recommendations

Consumer Reports® recommends the Honda Civic Si, based on reliability, safety and performance.

The Civic was chosen as a Car and Driver’s “Top Ten” for 2025 and 10 more times in the last 41 years. The K4 has never been chosen by Car and Driver in their “10Best” issue.

A group of representative automotive journalists from North America selected the Civic as the 2025 North American Car of the Year. The K4 has never been chosen.

The Honda Civic outsold the Kia K4 by almost 9 to one during 2024.

See Available Inventory