# Mercedes S-Class — Used Car Buying Guide

AutoScout's analysis of the Mercedes S-Class on the UK used-car market. Backed by 33 million DVSA MOT tests, current AutoTrader pricing, and depreciation curves derived from CAP/Glass's Guide data.

Live interactive report: https://autoscout.fyi/cars/mercedes-s-class

## Verdict

- **Best value year**: 2021
- **Ideal trim**: S500L AMG Line
- **Target mileage**: 30,000–50,000 miles
- **Max previous owners**: 2
- **Target price**: £55,000

## Why this model

The Mercedes S-Class is the epitome of luxury, offering an incredibly comfortable ride, a supremely quiet cabin, and cutting-edge technology. Buying a 3-4 year old model like the 2021 S500L AMG Line means you get all that prestige and performance for a fraction of its new price, making it fantastic value. It's built for long-distance cruising in ultimate comfort, making every journey feel special.

## What you should pay

Based on current UK market data for a 2021 S500L AMG Line with 30-50k miles, you should aim to pay around £55,000. This is a significant saving from new, as the S-Class takes a big hit in depreciation early on. Prices can vary by specification and condition, but this figure represents a strong market average for a well-maintained example.

## Which trim to buy

The S500L AMG Line is the sweet spot for a used S-Class. The 'L' denotes the long-wheelbase, giving you incredible rear legroom, perfect for passengers or just stretching out. The S500 engine provides ample power with the benefit of mild-hybrid assistance for better efficiency than pure petrol models. The AMG Line trim adds sportier styling elements, larger wheels, and often more luxurious interior touches, making it look and feel even more special without going overboard on running costs compared to the higher-performance AMG models.

## What to check before you buy

- Processor Starter/Generator issue (affecting some 2022 models)
- Touchscreen controls can take time to get used to
- Driver assistance systems can sometimes feel intrusive

## Running costs

Running an S-Class is never going to be cheap, but the S500L's mild-hybrid system helps a bit with fuel economy, offering around 45.6 mpg in real-world driving. Road tax is £200 per year. Insurance is in the highest group, 50, so expect substantial premiums. Servicing and parts will also be premium-priced, reflecting the car's luxury status and advanced technology.

## Key stats

- **Fuel Type**: Mild Hybrid
- **Horsepower**: 429 hp
- **Mpg**: 45.6 mpg
- **Reliability Score**: Good
- **Safety Rating**: 5-star Euro NCAP

## Trim comparison

| Trim | Price new | Price used | Key features |
| --- | --- | --- | --- |
| S350d AMG Line | £85,000 | £48,000 | Burmester surround sound system; Heated front seats; 360-degree camera |
| S450 AMG Line | £95,000 | £52,000 | AIRMATIC air suspension; MBUX infotainment system with augmented reality navigation; Soft-close doors |
| S500L AMG Line | £105,000 | £55,000 | Long wheelbase for enhanced rear legroom; Rear Executive package options (e.g., reclining seats, rear tablets); Nappa leather upholstery |

## Depreciation forecast

| Year | Estimated value | Retention |
| --- | --- | --- |
| 2026 | £55,000 | 0% |
| 2027 | £48,000 | 12.73% |
| 2028 | £42,000 | 12.5% |
| 2029 | £37,000 | 11.9% |
| 2030 | £33,000 | 10.81% |

The S-Class takes a massive hit in value during its first few years. By buying a 2021 model in 2026, you're letting the first owner absorb the steepest part of that depreciation curve. While it will continue to depreciate, the rate slows down considerably, offering a more stable ownership proposition for a luxury car.

Total value lost since new: 40%.

## Alternatives to consider

- [BMW 7 Series](https://autoscout.fyi/cars/bmw-7-series.md)
- [Audi A8](https://autoscout.fyi/cars/audi-a8.md)
- [Lexus LS](https://autoscout.fyi/cars/lexus-ls.md)

---

Source: AutoScout (https://autoscout.fyi). Part of a review of the UK used-car market across 500+ models.