Kia Rio vs Mercedes-Benz C-Class: Specs Compared

Also searched as Mercedes-Benz C-Class vs Kia Rio specs — both orientations show this same side-by-side comparison.

The Kia Rio is the more efficient of the two: it reaches 36 mpg combined versus 30 mpg for the Mercedes-Benz C-Class, a 6 mpg advantage and costs about $850 less per year to fuel.

Across 5 measured categories, the Kia Rio leads in 4. Figures are EPA test data, not manufacturer claims.

2015–2023

Kia Rio

Compact Cars · 17 configurations

36mpg combined (best)
All Kia Rio specs

2015–2027

Mercedes-Benz C-Class

Subcompact Cars · 123 configurations

30mpg combined (best)
All Mercedes-Benz C-Class specs

Head-to-head specifications

MetricKia RioMercedes-Benz C-Class
Best combined MPG36 mpg ✓30 mpg
Best city MPG33 mpg ✓28 mpg
Best highway MPG41 mpg ✓36 mpg
Lowest annual fuel costEPA estimate at 15,000 miles per year$1,700 ✓$2,550
Lowest CO2 output249 g/mi215 g/mi ✓
Engines offered1.6, SIDISIDI; Mild Hybrid, SIDI & PFI, SIDI; PHEV, SIDI
TransmissionsAutomatic (AV-S1), Automatic (variable gear ratios), Automatic (S6)Automatic 9-spd, Automatic 7-spd
DrivetrainsFront-Wheel DriveAll-Wheel Drive, Rear-Wheel Drive, 4-Wheel Drive
Fuel typesRegularPremium, Premium and Electricity
EPA classCompact CarsSubcompact Cars
Years covered2015–20232015–2027
Configurations on record17123

Source: EPA fuel economy records via fueleconomy.gov. Best-case values across all recorded configurations for each model.

Kia Rio vs Mercedes-Benz C-Class dimensions and size

The Mercedes-Benz C-Class is 28.3 inches longer than the Kia Rio on a wheelbase 11.4 inches longer, and 1,508 lbs heavier. Both clear the roughly 200 inches of usable length in a standard single garage bay.

Kia Rio versus Mercedes-Benz C-Class exterior dimensions
DimensionKia Rio (2024)Mercedes-Benz C-Class (2026)Difference
Length160.2 in188.6 in28.3 in
Width (excl. mirrors)68.1 in71.7 in3.5 in
Height57.1 in56.7 in0.4 in
Wheelbase101.6 in113 in11.4 in
Curb weight2,549 lbs4,057 lbs1,508 lbs

Width excludes mirrors; add 8–12 inches for mirrors out. Figures are for the newest model year on record for each vehicle. See both drawn to scale.

Kia Rio vs Mercedes-Benz C-Class: what the numbers mean

Running cost over five years: at the EPA's 15,000-mile-a-year assumption the Kia Rio burns about $1,700 of fuel annually against $2,550 for the Mercedes-Benz C-Class. That $850 yearly gap compounds to roughly $4,250 over five years and $6,800 over eight — often more than the price difference between two trims of the same vehicle, and the single largest running-cost line item separating these two.

City and highway economy: the Kia Rio leads in both cycles — 33 mpg city and 41 mpg highway against 28 and 36 mpg — so its fuel-efficiency advantage holds whether you commute in traffic or cover long highway miles.

Powertrain choice: the Kia Rio is recorded with 2 distinct engine configurations (1.6, SIDI), the Mercedes-Benz C-Class with 4 (SIDI; Mild Hybrid, SIDI & PFI, SIDI; PHEV). Across 17 recorded Kia Rio configurations and 123 for the Mercedes-Benz C-Class, the wider the engine spread the more the real-world fuel efficiency depends on which version you actually buy, so check the specific model year and drivetrain rather than the headline number.

Drivetrain and class: the Kia Rio is offered with Front-Wheel Drive, the Mercedes-Benz C-Class with All-Wheel Drive, Rear-Wheel Drive, 4-Wheel Drive. All-wheel drive typically costs one to two mpg combined against the same vehicle in front- or rear-wheel drive, which is worth remembering when the gap between these two is small. The EPA classes them as Compact Cars and Subcompact Cars respectively — the class drives the interior volume, cargo space and passenger space each one is measured against.

Tailpipe emissions: at their cleanest configurations the Mercedes-Benz C-Class emits 215 g/mile of CO2 versus 249 g/mile for the Kia Rio. Emissions track fuel consumption almost exactly, so the cleaner vehicle here is also the cheaper one to fuel.

Rio vs C-Class: common questions

Which is better on gas, the Kia Rio or the Mercedes-Benz C-Class?

The Kia Rio is the more efficient of the two: it reaches 36 mpg combined versus 30 mpg for the Mercedes-Benz C-Class, a 6 mpg advantage and costs about $850 less per year to fuel.

Which costs less to run per year?

By EPA estimates at 15,000 miles a year, the Kia Rio runs about $1,700 a year in fuel at its most efficient configuration, versus about $2,550 for the Mercedes-Benz C-Class — a difference of roughly $850 per year.

What engines do the Rio and C-Class offer?

Kia Rio: 1.6, SIDI. Mercedes-Benz C-Class: SIDI; Mild Hybrid, SIDI & PFI, SIDI; PHEV, SIDI.

Are they in the same vehicle class?

The EPA classifies the Kia Rio as Compact Cars and the Mercedes-Benz C-Class as Subcompact Cars, so they aren't a like-for-like match on size.

More Rio comparisons

More C-Class comparisons

Comparison id: kia-rio-vs-mercedes-benz-c-class