The swanky CLS-Class joined the Mercedes-Benz lineup in 2005 as a dramatically styled “four-door coupe” based on the E-Class. While this concept dates back to the British 1960s Rover P5, the CLS popularized the idea. The CLS and subsequent imitators from Audi, BMW and Volkswagen add two extra doors in the hopes of offering more practicality than traditional two-door coupes without sacrificing style, but the CLS’ low-slung shape dictates decidedly traditional coupe-like backseat room and trunk space.

The CLS was redesigned in 2019 and hasn’t changed much since. Like the previous two generations, it’s a looker from any angle.  Mercedes-Benz

The CLS entered its third generation in 2019, and while it retains its E-Class underpinnings, the car is sleeker and more stylish than before. Changes since 2019 have been mild, but Mercedes made meaningful improvements to the CLS’ infotainment and safety tech for 2021 including a refreshed interface and better functionality for important driver aids.  

Mercedes offers the 2021 CLS Coupe in two trims and with available all-wheel drive (AWD). The base CLS 450 starts at $71,350 while the AWD CLS 450 4Matic starts at $73,850. The faster Mercedes-AMG CLS 53 starts at $82,600, but comes only with AWD.

With only these two versions, the CLS’ standard features list reads like a luxury car greatest hits album. Highlights include 19-inch wheels, an adaptive suspension, a power sunroof, dual 12.3-inch displays, navigation, Apple CarPlay and Android Auto, remote start, heated front seats, a sport exhaust, blind spot assist, full-LED exterior lighting, a rearview camera and multiple USB-C inputs. 

Forward passengers in the Mercedes-Benz CLS 450 are treated to plenty of room, supportive seats, and a beautiful cockpit.  Mercedes-Benz

That said, the CLS is a Mercedes, so there are plenty of opportunities to push the price tag skyward and, curiously on so expensive a car, some features that come standard on some much cheaper cars cost extra here, including a $1,950 drivers assistance package. 

The real question for most buyers will be whether or not the CLS is a worthwhile upgrade from either the E-Class sedan or coupe, both of which are mechanically very similar but offer either more room or a traditional coupe body. Both cost less to start, with the E 450 sedan and coupe ringing in at $63,050 and $66,000, respectively.

Like those cars, the CLS 450 is powered by a turbocharged 3.0-liter inline-six with a 48-volt mild-hybrid system. That ultra-hyphenated engine produces 362 horsepower and 369 pound-feet of torque and sends it to either the rear or all four wheels through a nine-speed automatic transmission. 

 Dual 12.3-inch displays, for the gauges and the infotainment system, make for pretty and functional visuals. The recently-upgraded MBUX infotainment system is to learn and operate, too. Mercedes-Benz

Performance is strong, especially considering that there’s another level of go-power available in the AMG-tuned version of the car. The run to 60 mph from a standstill takes less than five seconds, and the mild-hybrid system adds a nice jolt of torque on takeoff. Mercedes provides five drive modes to tailor the experience to the driver’s whims, including Eco, Comfort, Sport, Sport Plus and a customizable Individual mode.

For those who want more speed, the AMG CLS 53 offers a more potent version of the same engine, with 429 horsepower and 384 pound-feet of torque channeled through a beefed-up nine-speed automatic. 2021 will be the final year of the AMG CLS 53, but it’s worth noting that the E-Class models also make this powertrain available.

Despite its vigorous performance, the CLS is relatively fuel-conscious, though it’s important to note that the mild-hybrid system does more to boost acceleration than economy. The standard car returns an EPA-estimated 23 mpg in the city, 30 mpg highway and 26 mpg combined, and all-wheel drive shaves one mpg from each figure. That’s 1 to 3 mpg shy of the Audi A7 and BMW 8 Series Gran Coupe. The AMG version runs similarly behind the Audi S7 but ahead of the M850i Gran Coupe.

 Rear passengers get supportive seats and plush accommodations, but precious little leg and head room considering that this is essentially a full-size sedan, particularly with the longer bumpers of the AMG variant. Mercedes-Benz

The CLS is one of the rare books that can be judged by its cover, as the interior is just as dramatically styled as the shapely sheet metal is outside. Woodgrain and leather coat the cabin and the standard ambient interior lighting system allows for several color combinations to accent the plush finishes. Deep, sculpted front seats offer excellent support, and standard heating makes the drive more comfortable for people living where the air hurts their faces for parts of the year. 

Though gorgeous, the CLS’ passenger accommodations ultimately disappoint when it comes to space. Yes, Mercedes added another seat in back by removing the center console, but with just 35.9 inches of rear headroom and 35 inches of rear legroom, all but the most tolerant adults will find cause to complain. The A7 and 8 Series Gran Coupe offer 1 to 2 inches more room in both dimensions.

The same issue is true with children in car seats. The extra doors promise more access than the E-Class two-door, but the CLS’ swoopy roof makes it head-bumpingly difficult to load and unload the back seat. 

The appeal of the CLS is in its style, but the gentle and muscular curves make it look even more low-slung and shapely than the related E-Class two-door coupe.  Mercedes-Benz

Mercedes updated the CLS’ infotainment software with the latest version of its MBUX interface, which brings smoother operation, a new touchpad controller and better speech recognition. It runs on a massive 12.3-inch display, which is accompanied by an equally imposing 12.3-inch configurable digital gauge cluster. The two are positioned side-by-side for a dramatic widescreen effect. Many goodies are standard, including Apple CarPlay and Android Auto, Bluetooth and navigation.

Neither IIHS nor NHTSA have evaluated the CLS, but the E-Class gets top marks from both agencies and we believe the CLS to be just as safe. The cars are well equipped out of the box, with standard adaptive high beam, a driver attention assist system, blind spot alerts, forward collision warnings and automatic emergency braking. 

That said, a highly sophisticated suite of other active-safety features are bundled in the driver assistance package. They include evasive steering, adaptive cruise control with stop and go and route-based speed adaptation, active blind spot monitoring with exit warnings and much more. These systems work very well, but you’ve got to ante up $1,950 to get them.