2018 Kia Optima: MPG and fuel economy

This page collects every fuel-economy figure the EPA publishes for the 2018 Kia Optima. Below you will find the headline combined, city, and highway MPG, the estimated annual fuel cost at three different driving levels, the tailpipe CO₂ emissions, and a full breakdown of the engine and drivetrain. The EPA rates 3 separate variants of this car (different engine, transmission, or drivetrain combinations), and you can compare them side by side in the trims table. If you want to know whether this generation got more or less efficient over the years, the year-over-year table further down covers every model year the EPA has rated.

Fuel economy at a glance

These are the EPA's official ratings for the 2018 Kia Optima. The numbers come from a standardised laboratory test cycle and are the same figures that appear on the window sticker of every new car. Real-world mileage varies with driving style, weather, fuel quality, and how heavily loaded the car is.

When the EPA tests several variants of the same nameplate (for example, a front-wheel-drive version and an all-wheel-drive version), each gets its own rating. The figures shown here are the headline variant, taken as the configuration with the best combined MPG. The trims table further down covers all 3 variants side by side.

Combined MPG is a 55/45 weighted blend of the city and highway test cycles. The EPA uses it as the single number you can compare across the entire dataset, including hybrids and EVs (which use the equivalent MPGe figure).

How the 2018 Kia Optima compares

The 2018 Kia Optima returns 31 combined MPG. Cars in the Large Cars class for the same model year average 26.5 MPG, which puts this car ahead of the class average by about 17%.

The most efficient car in the Large Cars class for the 2018 model year is the Tesla Model S 75D at 103 MPG. The bar chart below puts the Kia Optima alongside the class best and the class average so you can see the full picture.

For broader context, the average new car of the 2018 model year (across all classes) returns 25.6 MPG. Larger vehicles pull the all-cars average down, so do not use that figure on its own to judge a small car or a hybrid. The full list of the most efficient cars of the 2018 model year is on its own page.

Trim variants rated for 2018

The EPA rates 3 separate variants of the 2018 Kia Optima. The differences come from the engine size, transmission type, and drivetrain (front-wheel drive, all-wheel drive, and so on). The same nameplate can land several MPG apart depending on the configuration you actually buy.

The most efficient configuration on this page returns 31 MPG, while the least efficient returns 25 MPG. That is a spread of 6 MPG between trims of the same nameplate.

Annual fuel cost across driving patterns

The headline annual fuel cost the EPA publishes assumes 15,000 miles of driving per year and a fuel mix of 55% city and 45% highway. The dollar figure is calculated using the EPA's current reference price for regular gasoline, which is $3.99/gallon. EPA updates that reference periodically rather than tracking live pump prices, so treat it as a window-sticker estimate rather than today's pump number.

The table below scales the EPA's number to three common driving patterns. The combined MPG and the reference fuel price stay constant, only the annual mileage changes. To get a current-prices estimate, take your local gas price and multiply by 483.9 gallons (the car's annual consumption at the rated MPG).

Year-over-year MPG for the Kia Optima

The EPA has rated the Kia Optima across 20 model years, from 2001 Kia Optima through 2020 Kia Optima. The numbers below are the best combined MPG figure the EPA published for each year, which lets you see when the car was at its most efficient and how recent generations stack up.

The 2001 Kia Optima returned 21 MPG. The most recent 2020 Kia Optima returns 31 MPG. That is an improvement of 10 MPG over 19 model years, the kind of gain that usually comes from smaller engines, hybrid systems, or aerodynamic redesigns.

Compare against other Large Cars for 2018

If you are cross-shopping the 2018 Kia Optima, the most useful comparison is against the other cars in the Large Cars class for the same model year. The list below shows the highest-MPG peers, ranked from most to least efficient. Click any of them to open its full page.

The Tesla Model S 75D leads this group at 103 MPG, 72 MPG ahead of the 2018 Kia Optima.

Specifications

The 2018 Kia Optima runs a 1.6-liter 4-cylinder turbocharged engine paired with a automatic (am7), sending power through front-wheel drive.

Engine, transmission, and drivetrain together drive most of the variation in fuel economy across trims. A larger engine moves the car with less effort but burns more fuel. A turbo lets a small engine punch above its weight, often without much MPG penalty. All-wheel drive adds traction and weight, and usually costs a couple of MPG compared with two-wheel drive of the same engine.

Vehicle class

Large Cars

Engine

1.6L 4-cylinder turbocharged

Transmission

Automatic (AM7)

Drivetrain

Front-Wheel Drive

Fuel type

Regular

Annual petroleum use

9.6 barrels per year

Common questions about the 2018 Kia Optima

Quick answers to the questions people most often search for when looking up the 2018 Kia Optima.

• Is the 2018 Kia Optima fuel efficient?

  Yes. The 2018 Kia Optima returns 31 combined MPG, which beats the average car in the Large Cars class for the same model year by about 17%.
• What MPG does the 2018 Kia Optima get?

  The EPA rates the 2018 Kia Optima at 31 combined MPG, 28 MPG in city driving, and 37 MPG on the highway. Real-world numbers depend on your driving style, the weather, and how loaded the car is.
• How much does it cost to fuel a 2018 Kia Optima per year?

  The EPA estimates an annual fuel cost of $1,950 for the 2018 Kia Optima. That figure assumes 15,000 miles of driving per year, a 55% city and 45% highway split, and the EPA's published average fuel price for the rated fuel grade.
• What fuel does the 2018 Kia Optima use?

  The EPA lists the 2018 Kia Optima as running on regular gasoline. Using a different grade than the manufacturer specifies can affect fuel economy and engine longevity.
• Has the Kia Optima become more fuel efficient over time?

  Yes. The first EPA-rated Kia Optima, the 2001 Kia Optima, returned 21 combined MPG. The most recent 2020 Kia Optima returns 31 MPG, an improvement of 10 MPG over the run.
• How much CO₂ does the 2018 Kia Optima emit?

  Tailpipe CO₂ emissions are 286 g/mi. Multiplied across a typical year of driving (15,000 miles) that works out to about 4,290 kilograms of CO₂.
• What is the difference between the city and highway MPG of the 2018 Kia Optima?

  City driving returns 28 MPG and highway driving returns 37 MPG, a gap of 9 MPG. A spread that wide is typical of cars with conventional automatic or manual transmissions, where stop-start city traffic eats more fuel than a steady highway cruise.
• What engine is in the 2018 Kia Optima?

  The 2018 Kia Optima has a 1.6-liter 4-cylinder turbocharged engine (EPA description: SIDI). Smaller turbocharged engines like this one tend to deliver bigger-engine power on demand while keeping fuel economy closer to a non-turbo version of the same displacement.
• What transmission and drivetrain does the 2018 Kia Optima have?

  The 2018 Kia Optima comes with a automatic (am7) transmission and front-wheel drive.
• How does the 2018 Kia Optima compare to the best car in its class?

  The most efficient car in the Large Cars class for the 2018 model year is the Tesla Model S 75D at 103 combined MPG. The Kia Optima returns 31 MPG, a gap of 72 MPG. If you are comparing on fuel economy alone, the class leader is worth a look.

Source: U.S. EPA fuel economy dataset. Annual fuel cost figures assume 15,000 miles of driving per year and a 55% city, 45% highway split. Real-world mileage varies with driving conditions, vehicle maintenance, fuel quality, and driver behaviour.