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 (s/s) 2dr (187 bhp)
• Year: 2021
• Mileage: 38,735 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 has covered 38,735 miles, around 5,300 fewer miles than is typical for its age. The dealer is asking £22,600, which is £2,390 below the AskCar estimate of £24,990. To work out the AskCar estimate, we analyse UK dealer adverts for 1,826 BMW 4 Series cars across different ages and specifications. We first recorded this advert 56 days ago, and its asking price has since fallen by £1,800. Its advertised mileage matches the government's MOT record. You can find this car at Car Planet Barnet in New Southgate. How to contact the dealer and its opening hours are on this AskCar page.

Stock data as of 6 November 2026.

How we estimate prices and check cars

Price

Good value: £2,390 (9%) under the AskCar estimate of £24,990.

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 1,826 priced BMW 4 Series adverts across different ages and specifications, as of 6 November 2026.

A 2021 BMW 4 Series with the 2.0 diesel engine is typically advertised at £23,800: the median of the 148 for sale on AskCar, as of 6 November 2026.

Time on sale

This 2021 BMW 4 Series has been on sale for at least 56 days.

Price history

AskCar first saw this advert on 11 September 2026 at £24,400. Its asking price is now £22,600, £1,800 less. The latest price cut was seen on 2 November 2026.

Price changes recorded:

• 11 September 2026: £24,400
• 2 October 2026: £24,100
• 7 October 2026: £23,800
• 13 October 2026: £23,500
• 19 October 2026: £23,200
• 26 October 2026: £22,900
• 2 November 2026: £22,600

Mileage and MOT

MOT, from the government's MOT records (DVSA, the Driver and Vehicle Standards Agency), as of 6 November 2026: valid until 11 February 2027.

It failed its MOT on 12 February 2026 (nearside rear tyre has a cut in excess of the requirements deep enough to reach the ply or cords; offside front tyre has a bulge, caused by separation or partial failure of its structure) and passed later the same day.

Advisories at the latest test: offside rear tyre worn close to legal limit/worn on edge; nearside front tyre worn close to legal limit/worn on edge.

Mileage at that test: 30,490 miles, which matches the advertised 38,735 miles.

Advertised mileage is about 5,300 miles lower 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 6 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: £23,599, £999 more than 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, white. Mileage: 34,868 miles. Price: £22,795, £195 more than this car. Dealer: Williams Bmw Rochdale in Rochdale. AskCar page: https://askcar.co.uk/car/bmw-4-series-2021-d1c51114b60d
• 2021 BMW 4 Series M Sport, 2.0 diesel convertible, blue. Mileage: 44,855 miles. Price: £23,800, £1,200 more than this car. Dealer: Berry Heathrow in Heathrow. AskCar page: https://askcar.co.uk/car/bmw-4-series-2021-cbc9d8c6c160

• The nearest: 2021 BMW 4 Series M Sport, 2.0 diesel convertible, blue, 5 miles from this car. Mileage: 9,654 miles. Price: £28,745, £6,145 more than this car. Dealer: Group 1 Borehamwood BMW in Borehamwood. AskCar page: https://askcar.co.uk/car/bmw-4-series-2021-ae16c0438fca