2021 BMW 4 Series 2.0 420i M Sport

Overview

• Make: BMW
• Model: 4 Series
• Trim: M Sport
• Version: 2.0 420i M Sport Auto RWD Euro 6 2dr Step (181 bhp)
• Year: 2021
• Mileage: 68,323 miles
• Fuel: Petrol
• Body: Convertible, 2 doors, 4 seats
• Engine: 2.0 litres, 181 bhp
• Gearbox: Automatic
• Drive: Rear-wheel drive
• Colour: Black
• CO2: 154 g/km
• Emissions standard: Euro 6, ULEZ compliant

About this car

This 2021 BMW 4 Series M Sport has covered 68,323 miles, around 24,200 more miles than is typical for its age. The AskCar estimate for this car is £20,356. It is priced at £21,000, which is £644 above that estimate. The AskCar estimate uses UK dealer asking prices, including 1,814 BMW 4 Series adverts, and accounts for the car’s age, mileage and specification. This car was first seen in our listings data 8 days ago. Its advertised mileage matches the government's MOT record. How to contact the dealer and its opening hours are on this AskCar page.

Stock data as of 4 November 2026.

How we estimate prices and check cars

Price

Fair price: £644 (3%) over the AskCar estimate of £20,356.

The AskCar estimate is our expected asking price for this car. It uses UK dealer asking prices, accounting for make, model, trim, version, age, mileage, fuel, gearbox, body type, driven wheels, engine size and power. It is an advertised price, not a confirmed sale price.

It draws on 1,814 priced BMW 4 Series adverts across different ages and specifications, as of 4 November 2026.

A 2021 BMW 4 Series with the 2.0 petrol engine is typically advertised at £24,000: the median of the 144 for sale on AskCar, as of 4 November 2026.

Time on sale

This 2021 BMW 4 Series has been on sale for at least 8 days.

Price history

AskCar first saw this advert on 27 October 2026 at £21,000. Its asking price has not changed.

Mileage and MOT

MOT, from the government's MOT records (DVSA, the Driver and Vehicle Standards Agency), as of 4 November 2026: valid until 29 June 2027.

It has had 3 MOTs. The latest, on 26 June 2026, passed.

Advisories at the latest test: front brake disc worn, but not excessively; front windscreen damaged but not adversely affecting driver's view; offside rear nail in tyre.

Mileage at that test: 65,705 miles, which matches the advertised 68,323 miles.

Advertised mileage is about 24,200 miles higher than the median mileage of a 2021 BMW 4 Series on AskCar.

Similar cars

26 other 2021 BMW 4 Series M Sport 2.0 petrol automatic convertibles are for sale at UK dealers, from £18,990 to £33,950, as of 4 November 2026.

The 3 closest to this car in mileage:

• 2021 BMW 4 Series M Sport, 2.0 petrol convertible, black. Mileage: 65,000 miles. Price: £22,988, £1,988 more than this car. Dealer: West Kent Motor Group Online in Sevenoaks. AskCar page: https://askcar.co.uk/car/bmw-4-series-2021-dfed66a66f81
• 2021 BMW 4 Series M Sport, 2.0 petrol convertible, black. Mileage: 72,748 miles. Price: £20,999, the same price as this car. Dealer: Pro-Division Car Sales in Stirling. AskCar page: https://askcar.co.uk/car/bmw-4-series-2021-7396e5991916
• 2021 BMW 4 Series M Sport, 2.0 petrol convertible, white. Mileage: 58,943 miles. Price: £22,990, £1,990 more than this car. Dealer: Group 1 Southend BMW in Southend-on-Sea. AskCar page: https://askcar.co.uk/car/bmw-4-series-2021-088e831a7c9e