Kia K4 Review

The 2025 Kia K4 is a decisive stab into the heart of the compact-sedan segment

Jump To Special Features

Disruptor Design
2025 Kia K4 Pricing
Turbo Performance
Observations and Considerations
Interior Tech
Why Buy the 2025 Kia K4?
Specifications

BY MARK MAYNARD

The 2025 Kia K4 compact is a new nameplate backed by four generations of family ties. The ancestry of this small sedan goes back to its great, great, great grandparent, the Kia Sephia. It was the brand’s first automotive export to the U.S. from South Korea.

The fledgling Sephia was cheap — and not just inexpensive. The 1994 Kia Sephia was a $10,000 econobox advertised to be used, abused, and thrown out after the warranty expired. Back then, Kia’s new-vehicle warranty was 3-year/36,000-mile. Today, the warranty is 5 years/60,000 miles and 10 years/100,000 miles for powertrain coverage.

Four years later, Sephia — derived from the Greek “sapphire” — was redesigned for a short-lived second generation. It was replaced in 2000 and renamed Spectra, which would be redesigned and renamed Kia Forte.

Fourteen years and three generations later, the Forte was retired in 2024 and replaced by the K4. The alphanumeric nameplate now aligns with Kia’s passenger car nomenclature.

It’s such a long and winding road for such a small but significant car for Kia. Each generation builds upon the predecessor for the most dynamically styled and equipped fourth-generation 2025 K4. And a five-door hatchback is coming in late 2025.

The K4’s Disruptor Design

Among the K4 competitors are the Honda Civic, Mazda3, Toyota Corolla, and VW Jetta. It is evident that Kia benchmarked the Civic and went just a bit farther in developing the K4. The Honda Civic was the bestselling compact car in 2024, with around 242,000 cars sold. Annual sales of the 2024 Kia Forte totaled 106,050.

Kia says the K4 is the widest in the compact sedan segment and has the largest footprint. Its overall body design is distinct, with sleek aerodynamics. It is a breakaway design from the typical sedan body style. It shares its styling influence with the upcoming Kia EV4 battery-electric.

The K4 sedan has an overall length of 185.4 inches and is 72.8 inches wide. Front headroom is SUV tall at 39 inches without a sunroof or 37.3 inches with. Rear passengers have a class-leading 38 inches of legroom. Trunk space of 14.6 cubic feet is surpassed only by the Honda Civic at 14.8 cu.ft.

“By juxtaposing the K4’s fastback roofline and wide stance, we split the difference visually between the compact and midsize segments,” said Tom Kearns, chief designer, Kia Design Center America.

Exterior design elements include:

Vertically oriented LED headlights and taillights. The treatment is taken from the flagship EV9, re-creating sharp edges and bold lighting designs front and rear.

Hidden rear door handles in the C-pillar. The stealth handle placement is intended to emphasize the K4’s fastback proportions and its swept-back stance.

Rear sail panel. The K4’s rear quarter panel rises above the beltline to create a flying buttress (sail panel) treatment at the roofline. The sail panel’s angle meets the roof’s fastback slope for a contiguous style statement.

2025 Kia K4 Pricing

The 2025 Kia K4 compact sedan is sold in five trim levels, with two four-cylinder engine choices and two transmissions. All trim levels are front-wheel drive, with no all-wheel-drive option. The suggested retail pricing below includes the $1,175 freight charge from Pesqueria, Mexico.

The K4 LX, LXS, EX, and GT-Line, with a base powertrain of a 147-horsepower 2.0-liter four-cylinder engine and CVT, start at $23,165 to $26,365. The GT-Line Turbo starts at $29,265.

Find current Kia K4 pricing here.

And check for special offers and incentives here.

The base K4 LX is well equipped with such features as:

• 12.3-inch touchscreen infotainment screen with Kia Connect and satellite radio
• Wireless Apple CarPlay and Android Auto
• Smart Key with push-button start
• 4 USB-C charging ports
• Cloth seat upholstery
• Bluetooth wireless phone and music with multi-device connectivity
• Electric parking brake with auto-hold
• Heated side mirrors
• Rearview monitor

K4 GT-Line

Moving up to the K4 GT-line ($26,365) gives the look of the GT-line Turbo without the power. GT-Line features include:

• GT-Line sport steering wheel with paddle shifters
• Multilink rear suspension
• Unique exterior and interior design
• Black treatment to side mirrors, window surround, wheel moldings
• 1-inch larger rear disc brake rotors
• 18-inch alloy wheels with black machined finish
• GT-Line interior features include:
• SynTex and cloth seat upholstery
• Heated front seats
• 10-Way power driver’s seat with two-way power lumbar
• Wireless Phone Charger

Kia K4 GT-Line Turbo

The Kia K4 GT-Line Turbo ($29,265) is the sportiest K4 to date. It ups performance with a 190-hp, turbocharged 1.6-liter four-cylinder engine and eight-speed automatic transmission. Other K4 GT-Line Turbo upgrades include:

• 1-inch larger front and rear disc brakes. (16-inch ventilated front rotors, 15-inch solid rear rotors)
• Multilink rear suspension
• LED Cube Projection Headlights, LED Tail Lights, and LED Fog Lights
• Wide sunroof with power sunshade
• SynTex upholstery with heated front seats
• Alloy sport pedals
• 8-speaker Harman Kardon audio system

Today’s Kia K4 GT-Line Turbo tester costs $32,155, with options for Snow White Pearl paint, $395, and red interior package, $295. That’s a head-turning option for the handsome red on seats, portions of the steering wheel, and door panels.

Another worthwhile option on the tester is the GT-Line Turbo Technology Package, $2,200. It completes the driver-assist technologies for Level 2 semi-autonomous driving. The package includes:

• FCA Fusion+ for Forward Collision-Avoidance Assist
• Parking Distance Warning — front, rear, and side
• Blind-spot view monitor (shown in the garage array in the dials for speed and rpms when signaling left or right)
• Two memory presets for driver seat and side mirrors
• Ventilated front seats
• Multicolor ambient lighting
• Smartphone Digital Key 2.0

K4 Safety Features and Technologies

All K4 models have eight airbags, including standard rear side airbags. Standard driver-assist technologies include:

• Auto Emergency Braking Technology w/ Pedestrian & Cyclist Detection
• Intelligent Speed Limit Assist
• Smart Cruise Control with stop-and-go
• Lane keeping and following technologies
• High beam assist

2024 Kia K4 Powertrains

Base K4 models have a 147-horsepower Atkinson-cycle 2.0-liter four-cylinder engine with multi-point injection. The transmission is an Intelligent Variable Transmission (CVT) that simulates eight speeds.

The entry LX’s fuel-sipping mileage estimates are 30/40/34 mpg, dropping a blink to 29/39/33 mpg for the better-equipped EX and GT-Line.

The GT-Line Turbo has a 190-hp turbocharged 1.6-liter four-cylinder engine with a conventional (stepped) eight-speed automatic transmission.

GT-Line Turbo mileage estimates are 29/36/29 mpg using the recommended 87 octane fuel. In my 200-mile test week, I saw city fuel economy in the high 20s. I worked up to 38.7 mpg on the highway, which might have crept higher on longer commutes. Some owners have reported highway mileage of 48.3 mpg.

At 36 mpg highway, the daily commuter could expect a range of nearly 500 miles from the 12.4-gallon tank.

GT-Line Turbo Performance

The Turbo motor purrs at idle and never sounds harsh at highway speeds.

Driving in Normal power mode is focused on fuel economy with dutiful acceleration. Once I figured out that driving in Sport mode did not greatly impact my fuel economy, I never looked back. Sport sharpens throttle uptake for quicker starts from a stop.

At 70 mph, the Turbo engine spins at a reasonable 2,000 rpm. Cruising at 65 mph, the rpms are at a lanky 1,800 rpm, benefiting fuel economy.

The GT-Line Turbo performance does not provoke red-mist hooliganism. However, the car is well set up for enthusiastic driving. It puts its nose to the road to pull capably through fun cornering.

While there are paddle shifters, I did not feel the need to play Ricky Racer. But when I was out clipping corners, I did wish for a higher calling of Sport-plus mode. I wanted to use those paddle shifters to grab a lower gear with a hearty throttle blip to carry me through the turn.

GT-Line Turbo Ride and Handling

The side mirrors, which are offset from the body, offer open cornering views. The Turbo’s 18-inch wheels make the turning circle maneuverable at 36 to 37 feet. With the base 16-inch wheels, the span drops to 35.1 feet.

A notable asset of the GT-Line Turbo is its rear multilink suspension. It is more responsive in cornering than the dutiful torsion-beam axle in the non-turbo models. All K4 models have hydraulic twin-tube, gas-charged shock absorbers.

Highway cruising is settled and comfortable, but the multilink has the mettle for enthusiastic driving. It blends well-damped ride control with fluid weight transfers when diving into and out of corners. At times, the front suspension gave agile responses, but wow, hitting a pothole head-on returns a shocking jolt. More than once, I glanced at the gauge display for a possible blown tire. There was none.

While tearing up a backroad, there was no squawky complaining from the 18-inch Kumho Majesty grand touring tires. There is no distracting tire noise or harshness transferred to the cabin. These are all-season grand touring tires with a treadwear warranty of 6 years or 45,000 miles. Replacements will cost around $220 per tire.

K4 curb weights range from 2,956 pounds for the lower trims to 3,283 pounds for the loaded GT-Line Turbo. Bigger brakes, wheels, and an independent rear suspension add weight to the Turbo model.

Highway Driving Assist 2

Kia’s Highway Driving Assist 2 provides reliable and trustworthy Level 2 semi-autonomous driving. Lane centering is accurate and steers confidently through highway turns, with few transgressions over the white lines.

HDA2 is enabled with the GT-Line Turbo Technology Package, $2,200. It includes a worthwhile grouping of Smartphone Digital Key, two driver’s seat memory presets, ventilated front seats, a surround view monitor, a blind spot view monitor, and multicolor ambient lighting.

Interior Function

The Kia K4 is a compact that packs midsize substance. It has comfortable shoulder room and an open-air environment. Front headroom is 39 inches, or 37.1, with a sunroof. Front legroom is long, too, at 42.3 inches.

Settle into the driver’s seat for hours-long support without aggressive and confounding side and bottom bolsters. Among the 10-way power adjustments is seat-bottom tilt, not typically applied to small cars.

The rearview camera has 360-degree views, including overhead.

The GT-Line steering wheel has heft and padding where needed for a comfortable grip. The flat top opens sightlines at the base of the windshield, and the flat bottom gives thigh room.

Kia layered on the soundproofing. The treatment helps calm the cabin with dual-layer carpet and acoustic tires on the GT-Line models. An acoustic windshield is also available on the GT-Line Turbo and in the GT-Line Premium package.

Over-the-air updates are possible using the Kia Access app or through the Kia owner’s portal.

The tester came with the optional $175 floor mats, which are of good quality.

Observations and Considerations

There are old-school mechanical release levers for the trunk and fuel door. However, I do not like Kia’s Smart Trunk, the hands-free opener. Just stand at the trunk with key in pocket or purse, and the trunk gives a three-second chime before opening. Apparently, I walk too slowly because the very responsive trunk calibrations triggered an opening every time I walked past. However, the Smart Trunk has its moments, such as when walking up with multiple grocery bags in the rain. Fortunately, the Smart Trunk, a standard feature, can be canceled in the user settings.

When it rains, water droplets collect on the fast slope of the back window, complicating views through the dappled glass. Understandably, there is no rear wiper-washer, but the upcoming hatchback model will sweep away that situation.

With the bounty of features in the GT-Line Turbo, there is no heated steering wheel.

Rear AC outlets only on the GT-Line Turbo. Kia says the GT-Line Turbo was designed to appeal to midsize sedan shoppers who are OK with a slightly smaller vehicle. So the feature set aligns more with the midsize sedan segment. “None of our compact sedan competitors offer rear A/C vents on any trim,” Kia says.

Interior Tech

Upper trim levels of the K4 get the impressive Connected Car Navigation Cockpit (ccNC). The multi-segment display cockpit spans nearly 30 inches of digital display, another trickle-down from the EV9. A Quick Controls function for frequently used features works with a swipe on the screen.

The broad screenage makes a bold statement, divided into three unequal sections. However, it would be helpful if the sections could be moved around. The steering wheel obscures the left-side segment for heat-temp-AC control. The placement is of no consequence for right-hand-drive models. In this country, however, having to peer around the wheel to make adjustments gets old quickly.

Wireless Apple CarPlay and Android Auto are standard on all K4 models.

Use the Kia Connect voice assistant and say “Hey Kia” to access functions such as climate control and audio.

Back Seat and Trunk Space

For ride-share drivers, the rear legroom is a long 38 inches, which eases entry and exit. The seatback has a comfortable angle, but there is no seatback recline.

The GT-Line Turbo is unique in that it has rear AC vents, which are not provided on any other trim. Passengers will appreciate that feature and the dual charging USBs just below the vents.

There is a lot of trunk space at 14.6 cubic feet, but the trunk lid opens to just 16 inches. Fortunately, most luggage roller bags can be shoved in, but bigger bags will go to the back seat. Fold the 60/40 seatback for about 6 1/2 feet in length.

Why Buy the 2025 Kia K4?

Kia has created a segment disruptor with its K4. Compact sedans are a value purchase, but the K4 injects creative zhuzh — at a value price.

The 2025 Kia K4 will chew into Civic sales, but dethroning the segment champ will take time. The only things the K4 needs to challenge the Civic capably are a hatchback body style, a hybrid powertrain, and a hot version of the GT-Line Turbo.

Tap into the K4 owners’ group, k4owners.com.

2025 Kia K4 GT-Line Turbo Specifications

Body style: 4-door, 5-seat front-wheel-drive compact sedan

Engine: 190-hp 1.6-liter gasoline direct injection 4-cylinder; 195 lb.-ft. torque at 1,700-4,500 rpm

Transmission: 8-speed automatic with paddle shifters

Top speed: 130 mph

Fuel economy: 26/36/29 city/hwy/combined; 87 octane recommended

Coefficient of drag: 0.27 Cd

BY THE NUMBERS

Fuel tank: 12.4 gallons

Trunk space: 14.6 cubic feet

Front head/leg room: 37.1*/42.3 inches *w/sunroof

Rear head/leg room: 37/38 inches

Length/wheelbase: 185.4/107.1 inches

Curb weight: 3,283 pounds

Turning circle: 35.1 feet

FEATURES

Standard K4 GT-Line Turbo equipment includes: power sunroof with sunshade, LED Headlights-fog lights-combination taillights, SynTex upholstery, Harmon Kardon audio system, alloy sport pedals, rear air vents

Safety features include: Eight air bags (including standard rear side bags), auto emergency braking pedestrian and cyclist detection, smart cruise control with stop and go, Lane keeping and following, high beam assist

CHASSIS COMPONENTS

Brakes: Hydraulic, vacuum power-assisted 4-wheel discs; front, 16-inch ventilated rotors; rear, 15-inch solid rotors

Steering: Column-mounted, motor driven power assist (C-MDPS)

Tires-wheels: 18-inch all-season grand touring Kumho Majesty 9 Solus TA91, 235/40R; black alloy wheels

Suspension: front MacPherson struts; rear, multilink; hydraulic twin-tube, gas-charged shock absorbers (all trim levels)

PRICING

Base price: $29,265, including $1,175 freight charge; price as tested $32,155

Options on test vehicle: Snow White Pearl paint $395; GT-Line red interior color package $295; GT-Line Turbo Technology Package $2,200

Where assembled: Pesqueria, Mexico

Warranties: 5-years/60,000-miles bumper to bumper with roadside assistance; 10-years/100,000-miles powertrain