2021 Mercedes-Benz S-Class Reliability ReportCommon Problems, Repair Costs & Expert Verdict
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Quick Facts · 2021 Mercedes-Benz S-Class
- No active NHTSA safety recalls on record — a clean recall slate for the 2021 model year.
- Scores 5 points below the strongest nearby year — the 2020 Mercedes-Benz S-Class earns a 83.
- The system most likely to surface first: mbux / infotainment system (moderate severity).
The 2021 Mercedes-Benz S-Class at a glance
- Is the 2021 Mercedes-Benz S-Class reliable?
- Autojunket rates the 2021 Mercedes-Benz S-Class 78/100 (grade C+), categorized as moderate risk. A technological marvel offering unparalleled luxury, but its bleeding-edge systems present a significant financial commitment for long-term reliability.
- Should I buy a used 2021 Mercedes-Benz S-Class?
- Autojunket recommends reading the full reliability report before buying a 2021 Mercedes-Benz S-Class. The 2021 Mercedes-Benz S-Class represents the pinnacle of luxury and technology, but it demands an owner who is prepared for the high costs associated with maintaining such a sophisticated machine. While fundamentally well-engineered, its complexity introduces numerous potential points of failure that can lead to ey…
- Which Mercedes-Benz S-Class years are the most reliable?
- Best model years to buy: For the W223 generation, generally 2023+ as early model year kinks may be ironed out.. Years to avoid: First model year (2021) for those highly risk-averse, due to the introduction of substantial new technology..
- What are the most common problems with the 2021 Mercedes-Benz S-Class?
- The top failure points on the 2021 Mercedes-Benz S-Class are MBUX / Infotainment System (typically around 15,000-45,000 miles), Air Suspension (Airmatic/E-Active Body Control) (typically around 50,000-90,000 miles), Advanced Driver-Assistance Systems (ADAS) (typically around 30,000-70,000 miles). Autojunket's full report includes repair-cost ranges and inspection checklists for each.
- At what mileage do problems start on the 2021 Mercedes-Benz S-Class?
- The first major mileage danger zone for the 2021 Mercedes-Benz S-Class is around 30,000. Early Software & Electrical Kinks — At this stage, any initial software bugs or minor electrical gremlins from the new W223 generation tend to surface. These are often fixable with dealer updates but can be frustrating. Early brake wear may also become evident.
Every answer is generated from real repair, recall, and ownership data — full breakdown in the report.
Read the full free reportShould You Buy the 2021 Mercedes-Benz S-Class?
The 2021 Mercedes-Benz S-Class, while a paragon of luxury and technological advancement, carries a moderate risk profile for long-term ownership. Its cutting-edge features and complex systems provide an unparalleled experience but demand meticulous maintenance and a substantial budget for potential repairs. This isn't a vehicle you can neglect; it's a testament to engineering that requires ongoing commitment to truly shine.
The 2021 Mercedes-Benz S-Class represents the pinnacle of luxury and technology, but it demands an owner who is prepared for the high costs associated with maintaining such a sophisticated machine. While fundamentally well-engineered, its complexity introduces numerous potential points of failure that can lead to ey…
Best Model Years
For the W223 generation, generally 2023+ as early model year kinks may be ironed out.
Years to Avoid
First model year (2021) for those highly risk-averse, due to the introduction of substantial new technology.
Biggest Strengths
- Unmatched build quality and luxury materials
- Exceptional ride comfort and refinement
- Robust powertrain fundamentals (engine/transmission)
Top Risk Areas
The systems that tend to fail first on the 2021 Mercedes-Benz S-Class, with the typical mileage window when each becomes a concern. Detailed repair-cost ranges and exact what-to-check inspection notes are in the full report.
The sophisticated MBUX system, with its numerous screens and extensive functionality, can suffer from software glitches, freezing, or slow responsiveness. These often require dealer diagnostics and software updates, or in some cases, mod…
The advanced air suspension, while providing incredible comfort, is prone to air spring leaks, compressor failures, or sensor malfunctions. Symptoms include uneven ride height, prolonged compressor noise, or a 'rough' ride. Repairs are e…
The multitude of radar, camera, and ultrasonic sensors for features like adaptive cruise control, lane keeping, and parking assist can develop faults. This might manifest as sporadic warnings, system deactivation, or incorrect readings,…
2021 Mercedes-Benz S-Class Mileage Danger Zones
The mileage windows when the 2021 Mercedes-Benz S-Class most commonly needs attention. Plan ahead, budget accordingly, and inspect before you cross each threshold.
Early Software & Electrical Kinks
At this stage, any initial software bugs or minor electrical gremlins from the new W223 generation tend to surface. These are often fixable with dealer updates but can be frustrating. Early brake wear may also become evident.
Major Service & Component Wear
This mileage often coincides with significant maintenance intervals (e.g., transmission fluid, spark plugs). Suspension components like bushings may start showing wear, and the air suspension system should be closely monitored for early…
Elevated Risk & Luxury Component Fatigue
Beyond 90k, the risk of major components failing increases significantly. Air springs are likely candidates for replacement, as are other expensive electronic modules. Expect potential for costly repairs in key luxury features.
High Risk - Major Overhaul Expected
At this mileage, the vehicle will likely require significant investment to maintain its peak performance and reliability. Major drivetrain components, extensive suspension work, and comprehensive electrical diagnostics are often necessar…
2021 Mercedes-Benz S-Class Ownership Cost Outlook
What it typically costs to keep the 2021 Mercedes-Benz S-Class on the road. Full 5-year cost-of-ownership projection and major-failure-risk forecast are in the report.
Annual Maintenance
$1,000-1,800
Moderate Repairs
$1,500-4,000 occasionally
How Long Does the 2021 Mercedes-Benz S-Class Last?
For a used 2021 S-Class, prioritize vehicles with lower mileage (under 40,000 miles) and a clear, verifiable Mercedes-Benz dealer service history. Higher mileage examples will offer significant savings on purchase price but come with a dramatically increased probability of immediate, high-cost repairs, especially fo…
What 2021 Mercedes-Benz S-Class Owners Actually Say
What Owners Love
- Unrivaled ride comfort and serene cabin quietness
- Exceptional interior quality, materials, and ambient lighting
- Cutting-edge technology and infotainment features (when working reliably)
- Powerful engine options with smooth, refined performance
Common Frustrations
- Exorbitant cost of routine maintenance and unexpected repairs
- MBUX system can be overly complex and prone to occasional glitches
- Rapid depreciation, especially in the first few years
- Expensive replacement parts for brakes and tires
Who Should Buy the 2021 Mercedes-Benz S-Class?
Best For
- Luxury enthusiasts prioritizing comfort and technology above all else
- Individuals who lease and return vehicles before warranty expiration
- Buyers with substantial disposable income for maintenance and repairs
Not Ideal For
- Budget-conscious buyers looking for low operating costs
- Owners who prefer to perform their own maintenance or use independent shops frequently
How the 2021 Mercedes-Benz S-Class Compares to Rivals
The S-Class offers a more sophisticated and luxurious experience than most rivals, especially in terms of cutting-edge technology and interior opulence. However, this comes at the cost of higher complexity and potentially higher long-term maintenance and repair expenses compar…
More Reliable Than
- Maserati Quattroporte
- Older generations of S-Class (W220, W221, first model years of W222)
Comparable To
- BMW 7 Series (G70 generation)
- Audi A8 (D5 generation)
NHTSA Recalls
No active NHTSA safety recalls on file for the 2021 Mercedes-Benz S-Class. Always verify with your VIN atnhtsa.gov.
What breaks on the 2021 Mercedes-Benz S-Class?
Full reliability breakdown — engine, transmission, rust, electrical. With repair costs and mileage danger zones.
Autojunket OSC · OSC Transfer
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Mercedes-Benz S-Class by Year
Compare AutoScores across nearby years of the Mercedes-Benz S-Class. Click any year for its full report.
If You're Considering This, Also Look At
Similar class, similar year range — ranked by AutoScore.
Relevant Products for Your 2021 Mercedes-Benz S-Class
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Where the 2021 Mercedes-Benz S-Class report beats Carfax + CR
Carfax tells you if it crashed. Consumer Reports rates the whole nameplate. Autojunket tells you what will actually break on this specific year — and how to negotiate it.
Year-specific reliability score
Common problems + repair costs
Mileage danger zone map
AI negotiation script + walk-away price
Single report price
Frequently Asked Questions
Related Comparisons
Sell your 2021 Mercedes-Benz S-Class for what it's actually worth.
Log every service on your Mercedes-Benz S-Class. When it's time to sell, hand the buyer a signed PDF — every receipt, mileage-verified, close the deal at your price.
- OSC Transfer PDF — every receipt
- Snap-a-receipt AI log
- Fuel & mileage tracker
- Shareable buyer view link
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