Cadillac CT5 vs Mercedes-Benz CLS-Class: Specs Compared
Also searched as Mercedes-Benz CLS-Class vs Cadillac CT5 specs — both orientations show this same side-by-side comparison.
The Cadillac CT5 is the more efficient of the two: it reaches 27 mpg combined versus 26 mpg for the Mercedes-Benz CLS-Class, a 1 mpg advantage and costs about $100 less per year to fuel.
Across 5 measured categories, the Cadillac CT5 leads in 4. Figures are EPA test data, not manufacturer claims.
2015–2023
Mercedes-Benz CLS-Class
Compact Cars · 27 configurations
Head-to-head specifications
| Metric | Cadillac CT5 | Mercedes-Benz CLS-Class |
|---|---|---|
| Best combined MPG | 27 mpg ✓ | 26 mpg |
| Best city MPG | 23 mpg | 24 mpg ✓ |
| Best highway MPG | 33 mpg ✓ | 31 mpg |
| Lowest annual fuel costEPA estimate at 15,000 miles per year | $2,800 ✓ | $2,900 |
| Lowest CO2 output | 333 g/mi ✓ | 334 g/mi |
| Engines offered | SIDI | SIDI; Mild Hybrid, SIDI |
| Transmissions | Automatic (S10), Manual 6-spd | Automatic 9-spd, Automatic 7-spd |
| Drivetrains | All-Wheel Drive, Rear-Wheel Drive | All-Wheel Drive, 4-Wheel Drive, Rear-Wheel Drive |
| Fuel types | Premium | Premium |
| EPA class | Midsize Cars | Compact Cars |
| Years covered | 2020–2026 | 2015–2023 |
| Configurations on record | 52 | 27 |
Source: EPA fuel economy records via fueleconomy.gov. Best-case values across all recorded configurations for each model.
Cadillac CT5 vs Mercedes-Benz CLS-Class dimensions and size
The Mercedes-Benz CLS-Class is 0.8 inches longer than the Cadillac CT5 on a wheelbase 3.1 inches shorter, and 478.4 lbs heavier. Both clear the roughly 200 inches of usable length in a standard single garage bay.
| Dimension | Cadillac CT5 (2026) | Mercedes-Benz CLS-Class (2018) | Difference |
|---|---|---|---|
| Length | 193.7 in | 194.5 in | 0.8 in |
| Width (excl. mirrors) | 74 in | 74 in | identical |
| Height | 57.1 in | 55.9 in | 1.2 in |
| Wheelbase | 116.1 in | 113 in | 3.1 in |
| Curb weight | 3,799 lbs | 4,277 lbs | 478 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.
Cadillac CT5 vs Mercedes-Benz CLS-Class: what the numbers mean
Running cost over five years: at the EPA's 15,000-mile-a-year assumption the Cadillac CT5 burns about $2,800 of fuel annually against $2,900 for the Mercedes-Benz CLS-Class. That $100 yearly gap compounds to roughly $500 over five years and $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 versus highway split: the Mercedes-Benz CLS-Class is the stronger commuter at 24 mpg city, while the Cadillac CT5 pulls ahead on the interstate at 33 mpg highway. If most of your driving is stop-and-go traffic the city figure is the one to weigh; for long-distance highway mileage the reverse is true, and the two vehicles effectively swap places depending on how you drive.
Powertrain choice: the Cadillac CT5 is recorded with 1 distinct engine configuration (SIDI), the Mercedes-Benz CLS-Class with 2 (SIDI; Mild Hybrid, SIDI). Across 52 recorded Cadillac CT5 configurations and 27 for the Mercedes-Benz CLS-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 Cadillac CT5 is offered with All-Wheel Drive, Rear-Wheel Drive, the Mercedes-Benz CLS-Class with All-Wheel Drive, 4-Wheel Drive, Rear-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 Midsize Cars and Compact 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 Cadillac CT5 emits 333 g/mile of CO2 versus 334 g/mile for the Mercedes-Benz CLS-Class. Emissions track fuel consumption almost exactly, so the cleaner vehicle here is also the cheaper one to fuel.
CT5 vs CLS-Class: common questions
Which is better on gas, the Cadillac CT5 or the Mercedes-Benz CLS-Class?
The Cadillac CT5 is the more efficient of the two: it reaches 27 mpg combined versus 26 mpg for the Mercedes-Benz CLS-Class, a 1 mpg advantage and costs about $100 less per year to fuel.
Which costs less to run per year?
By EPA estimates at 15,000 miles a year, the Cadillac CT5 runs about $2,800 a year in fuel at its most efficient configuration, versus about $2,900 for the Mercedes-Benz CLS-Class — a difference of roughly $100 per year.
What engines do the CT5 and CLS-Class offer?
Cadillac CT5: SIDI. Mercedes-Benz CLS-Class: SIDI; Mild Hybrid, SIDI.
Are they in the same vehicle class?
The EPA classifies the Cadillac CT5 as Midsize Cars and the Mercedes-Benz CLS-Class as Compact Cars, so they aren't a like-for-like match on size.
More CT5 comparisons
More CLS-Class comparisons
Comparison id: cadillac-ct5-vs-mercedes-benz-cls-class