Kia K4 Fuel Economy (MPG)
What is the real-world gas mileage of a 2026 Kia K4?
The 2026 Kia K4 gets up to 34 MPG combined (30 city / 40 highway) in EPA testing.
Latest model year (2026):
The Kia K4 gets up to 33 MPG combined (29 city / 39 highway) in the Auto (AV-S1), 4 cyl, 2.0 L trim.
Kia K4 MPG — All Years
| Year | Trim | Engine | Fuel | City (MPG) | Hwy (MPG) | Combined (MPG) |
|---|---|---|---|---|---|---|
| 2026Config 1 of 5 | Auto (AV-S1), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 29 | 39 | 33 |
| 2026Config 2 of 5 | Auto (AV-S1), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 29 | 39 | 33 |
| 2026Config 3 of 5 | Auto (AV-S1), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 28 | 34 | 30 |
| 2026Config 4 of 5 | Auto (S8), 4 cyl, 1.6 L | 4 1.6L | Regular Gasoline | 26 | 33 | 28 |
| 2026Config 5 of 5 | Auto (S8), 4 cyl, 1.6 L | 4 1.6L | Regular Gasoline | 26 | 33 | 28 |
| 2025Config 1 of 3 | Auto (AV-S1), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 29 | 39 | 33 |
| 2025Config 2 of 3 | Auto (AV-S1), 4 cyl, 2.0 L | 4 2.0L | Regular Gasoline | 30 | 40 | 34 |
| 2025Config 3 of 3 | Auto (S8), 4 cyl, 1.6 L | 4 1.6L | Regular Gasoline | 26 | 36 | 29 |
Data sourced from fueleconomy.gov (U.S. Department of Energy). MPG figures are EPA-tested. Fuel costs are estimates based on average fuel prices and 15,000 miles/year.
Kia K4 data analysis
How Kia K4 combined fuel economy varies
Across 8 configurations recorded for the 2025 through 2026 Kia K4, combined fuel economy runs from 28 MPG to 34 MPG. The strongest figure belongs to the 2025 Kia K4 (Auto (AV-S1), 4 cyl, 2.0 L) at 34 MPG, and the weakest to the 2026 car (Auto (S8), 4 cyl, 1.6 L) at 28 MPG — a spread of 21%. A gap that wide means the model year and configuration you buy matter more than the nameplate does: quoting a single number for the Kia K4 would be misleading.
What changed for 2026
Average combined fuel economy for the 2026 Kia K4 is 30.4 MPG, against 32 MPG for the 2025 car — it fell by 1.6 MPG. Buyers who care most about this figure should look at the earlier model years in the table above before assuming newest is best.
How to read this Kia K4 data
This page lists every 2025 through 2026 Kia K4 record we hold for this measurement — 8 rows in total, one per configuration and model year rather than a single headline figure. Figures are published as the source agency records them: we do not round, average or interpolate missing years, and a year that is absent from the table is a year with no published measurement rather than a zero. Where a manufacturer offered several drivetrains or body styles in the same year, each appears on its own row, because those variants rarely share the same numbers.
Configurations behind these Kia K4 numbers
The 2025 through 2026 Kia K4 entries here cover the variants Auto (AV-S1), 4 cyl, 2.0 L and Auto (S8), 4 cyl, 1.6 L. 2026 is the busiest model year in the record with 5 separate measured configurations, which is why a single quoted combined fuel economy figure for that year is rarely the one that matches the car in front of you. Match the row to the exact drivetrain, body style and engine on the window sticker or VIN before relying on the number, and use the comparison links below to see how those same configurations line up against rival models.
Where these Kia K4 figures come from
Every value on this page is loaded from federal open data — EPA fuel economy submissions, NHTSA vehicle and crash-test records, and manufacturer specification filings — rather than dealer listings or copied editorial content. The Kia K4 record refreshes as the agencies publish, which typically means new model-year rows appear in the autumn and crash-test results follow through the model year as vehicles are tested. Because certification data is filed per configuration, treat any single headline number for this vehicle with caution: the figure that applies to a specific car depends on its engine, drivetrain, body style and model year, all of which are listed separately above. If a number here disagrees with a brochure, the brochure is usually quoting the best available configuration rather than the one being sold.
Official Factory Specs vs. AutoSpecData Expert Benchmarks
The EPA highway loop never holds interstate speed. Here is what the same engine does when you sit on the cruise control.
| Cruise speed | EPA highway spec | AutoSpecData adjusted MPG | Fuel you lose |
|---|---|---|---|
| 60 mph | 40 MPG | 40 MPG | 0% |
| 65 mph | 40 MPG | 37.3 MPG | 7% |
| 70 mph | 40 MPG | 34.7 MPG | 13% |
| 75 mph | 40 MPG | 32.4 MPG | 19% |
| 80 mph | 40 MPG | 30.2 MPG | 25% |
Our Real-World Speed MPG Adjuster re-scales the Kia K4 EPA highway result with a quadratic drag term (mpg = hwy ÷ (1 + k·(v² − 60²)/60²), k = 0.55 for trucks, SUVs and vans, 0.42 for cars). Wind, roof racks, and a heavy right foot make it worse, never better.
Frequently Asked Questions About K4 MPG
What is the MPG of the Kia K4?
The Kia K4 gets up to 34 MPG combined (30 city / 40 highway) in the 2026 model year. Fuel economy varies by engine and trim — see the full table above for details.
Which Kia K4 trim has the best fuel economy?
The Auto (AV-S1), 4 cyl, 2.0 L trim offers the best combined fuel economy at 34 MPG. Smaller engines and front-wheel-drive configurations typically achieve the highest MPG.