843 on UK roads in 2025-5 vs 2024
On the road
843
843 licensed
Change vs 2024
-0.6%
-5 cars
New in 2025
4
first-time registrations
Electrified
0%
hybrid, plug-in & battery
The Mercedes 400 is an uncommon sight on UK roads, with 843 licensed in 2025 - down 0.6% on 2024. 4 were registered new in 2025. The fleet is overwhelmingly petrol (98%), with most in the Over 3.0L class. Most date from the Before 2000 era.
Licensed Mercedes 400 cars on the road over time
First-time registrations per year
Fuel, engine size and age across every Mercedes 400 on the road today.
Current split
Engine size
Cars on the road by engine capacity
How old are they?
Share of cars by the year they were first registered
How a Mercedes 400 holds up at its MOT and how it's driven - from 21 tests, tracked across 2022-2025.
Average for its class
84.2%
21 MOT tests in 2025 · 19 first-time
Pass rate over time
2022
100%
2023
84.2%
2024
83.3%
2025
84.2%
▼ 15.8 pts since 2022
First-time pass rate by the car's age (tested in 2025)
Too new for an age breakdown - most haven't reached MOT age (3 years) yet, so there isn't enough history to chart.
How a Mercedes 400 is driven
tracked across 2022-25miles a year, from 16 cars tracked across years
68.8%
low · <5k
31.3%
avg · 5-15k
0%
high · 15k+
Most cover 570-5,339 miles a year (median 1,421).
Yearly mileage as the car ages
Driven most when newer, easing as it gets older.
Mileage & condition
Odometer when tested (2025)
Typical odometer rising: 98,990 → 100,120 → 113,388 → 83,547
Pass rate as the odometer climbs
First-time pass rate by fuel
Not enough data.
A 2025 Mercedes 400 passes first time 84.2% of the time - above the 77.6% UK average, and easing slightly year on year. The typical one is driven about 3,066 miles a year, and reliability is mostly about miles: 100% of low-mileage cars pass versus 75% past 120k.
Of 3 first-time fails, here's what gets flagged most. Most cars fail on more than one item, so shares add up past 100%.
Share of failed tests, by area
Exact items most often recorded as the reason a car failed
Before you buy a specific Mercedes 400, run its registration through AnalyzeMyCar for MOT history, mileage checks, service history and valuation.
