2021 BMW 4 Series 2.0 420d MHT M Sport

Overview

• Make: BMW
• Model: 4 Series
• Trim: M Sport
• Version: 2.0 420d MHT M Sport Auto RWD Euro 6 2dr (187 bhp)
• Year: 2021
• Mileage: 44,855 miles
• Fuel: Diesel, mild hybrid
• Body: Convertible, 2 doors, 4 seats
• Engine: 2.0 litres, 187 bhp
• Gearbox: Automatic
• Drive: Rear-wheel drive
• Colour: Blue
• CO2: 129 g/km
• Emissions standard: Euro 6, ULEZ compliant

About this car

This 2021 BMW 4 Series M Sport is advertised with 44,855 miles on the clock. The AskCar estimate for this car is £23,855. It is priced at £23,800, which is £55 below that estimate. The AskCar estimate draws on 1,833 BMW 4 Series adverts across the UK, adjusting for age, mileage, trim, engine and other specifications. Since we first spotted the advert 90 days ago, the asking price has dropped by £3,195. We checked its advertised mileage against the government's MOT record, and they match. It is advertised by Berry Heathrow in West Drayton. How to contact the dealer and its opening hours are on this AskCar page.

Stock data as of 5 November 2026.

How we estimate prices and check cars

Price

Fair price: £55 (under 1%) under the AskCar estimate of £23,855.

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 1,833 priced BMW 4 Series adverts across different ages and specifications, as of 5 November 2026.

A 2021 BMW 4 Series with the 2.0 diesel engine is typically advertised at £24,000: the median of the 149 for sale on AskCar, as of 5 November 2026.

Time on sale

This 2021 BMW 4 Series has been on sale for at least 90 days.

Price history

AskCar first saw this advert on 7 August 2026 at £26,995. Its asking price is now £23,800, £3,195 less. The latest price cut was seen on 23 October 2026.

Price changes recorded:

• 7 August 2026: £26,995
• 28 August 2026: £26,400
• 19 September 2026: £25,800
• 6 October 2026: £24,800
• 23 October 2026: £23,800

Mileage and MOT

MOT, from the government's MOT records (DVSA, the Driver and Vehicle Standards Agency), as of 5 November 2026: valid until 2 December 2026.

It has had 2 MOTs. The latest, on 14 November 2025, passed.

Advisories at the latest test: nearside front seat belt webbing slightly damaged or frayed; offside front seat belt webbing slightly damaged or frayed.

Mileage at that test: 38,550 miles, which matches the advertised 44,855 miles.

Advertised mileage is about 800 miles higher than the median mileage of a 2021 BMW 4 Series on AskCar.

Similar cars

6 other 2021 BMW 4 Series M Sport 2.0 diesel automatic convertibles are for sale at UK dealers, from £21,999 to £28,745, as of 5 November 2026.

The 3 closest to this car in mileage:

• 2021 BMW 4 Series M Sport, 2.0 diesel convertible, blue. Mileage: 41,650 miles. Price: £23,799, the same price as this car. Dealer: Fords Of Winsford Car Supermarket in Winsford. AskCar page: https://askcar.co.uk/car/bmw-4-series-2021-b356ce1f181f
• 2021 BMW 4 Series M Sport, 2.0 diesel convertible, black. Mileage: 49,000 miles. Price: £23,250, £550 less than this car. Dealer: Family Autos Sports and Prestige in Brigg. AskCar page: https://askcar.co.uk/car/bmw-4-series-2021-9794d26f8203
• 2021 BMW 4 Series M Sport, 2.0 diesel convertible, blue. Mileage: 38,735 miles. Price: £22,600, £1,200 less than this car. Dealer: Car Planet Barnet in Barnet. AskCar page: https://askcar.co.uk/car/bmw-4-series-2021-146d187a836c

• The nearest: 2021 BMW 4 Series M Sport, 2.0 diesel convertible, blue, 13 miles from this car. Mileage: 9,654 miles. Price: £28,745, £4,945 more than this car. Dealer: Group 1 Borehamwood BMW in Borehamwood. AskCar page: https://askcar.co.uk/car/bmw-4-series-2021-ae16c0438fca