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2021 Mercedes-benz C-class Cabriolet
Solid pick. The public record on this car is clean for its age. Inspect it, then negotiate with confidence.
13 owner complaints · 0 recalls · data verified July 14, 2026 · source: NHTSA
Why buy?
Complaints are still coming in strong late in this car's life, a chronic-problem pattern, not early teething.
Very few owner complaints for its age and sales volume.
Zero recalls, rare for a car this age.
The math, shown
Full methodology →Complaints filed per year
Fading = early teething worked out. Climbing = problems aging in.
How it crashes
NHTSA’s own crash tests, separate from the reliability score above.
NHTSA crash-tested this model year but didn’t publish an overall star rating for it.
Source: nhtsa.gov/ratings. Star ratings compare vehicles within the same class and size, not across every car on the road.
The road ahead
What breaks on a 2021 Mercedes-benz C-class Cabriolet, plotted where owners report it happening.
Mileage medians come from owners who mentioned an odometer reading in their NHTSA complaint, a rough guide, not a schedule.
Engine
54%7 complaints · typically near 42k mi · 4 in the last 2 years
“2021 Mercedes-Benz C300 with M254 2.0L turbo engine experienced sudden cylinder head failure at 44,000 miles due to manufacturing porosity in the cylinder head and cam…”
Fuel system
23%3 complaints · 3 in the last 2 years
“While driving car on Sunday 10/5, it suddenly failed to respond to gas pedal pressure. The car stopped accelerating and rather slowed to 15 MPH, almost causing a car f…”
Visibility & wipers
8%1 complaints · 1 in the last 2 years
“I am reporting a safety defect involving the panoramic sunroof on my 2021Mercedes-Benz Coop vehicle. The panoramic sunroof has malfunctioned due to an apparent design …”
Transmission & drivetrain
8%1 complaints · 1 in the last 2 years
“My C300 only had about 42,000 miles and was less than 5 years old. Just after the factory warranty expired, the engine was running rough and hot, and "check engine" li…”
Recalls (0)
No recall campaigns on file for this model year.
Before you hand over money
Check the VIN for open recalls
NHTSA’s free lookup shows whether this exact car had its recall remedies completed.
Free NHTSA VIN check ↗Get a pre-purchase inspection
A $150 to $250 independent inspection of this exact 2021 Mercedes-benz C-CLASS CABRIOLET beats every score on the internet, including ours.
What to ask forNot set on the 2021? See how every C-class Cabriolet model year scores →
Cross-shopping? Compare the 2021 Mercedes-benz C-class Cabriolet against another car →
What owners say
Real owners of this exact model-year, shown separately from the NHTSA score. If they disagree, that’s worth knowing.