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 (s/s) 2dr (181 bhp)
• Year: 2021
• Mileage: 17,141 miles
• Fuel: Petrol
• Body: Convertible, 2 doors, 4 seats
• Engine: 2.0 litres, 181 bhp
• Gearbox: Automatic
• Drive: Rear-wheel drive
• Colour: Grey
• CO2: 160 g/km
• Emissions standard: Euro 6, ULEZ compliant

About this car

This 2021 BMW 4 Series M Sport is advertised with 17,141 miles, approximately 26,500 below the typical mileage for its age. Its asking price of £28,800 is £1,601 above the AskCar estimate of £27,199. The AskCar estimate draws on 1,805 BMW 4 Series adverts across the UK, adjusting for age, mileage, trim, engine and other specifications. Since we first spotted the advert 3 days ago, the asking price has dropped by £500. We checked its advertised mileage against the government's MOT record, and they match. The seller is MINI UK at Vertu Exeter MINI, based in Exeter. How to contact the dealer and its opening hours are on this AskCar page.

Stock data as of 9 November 2026.

How we estimate prices and check cars

Price

Fair price: £1,601 (5%) over the AskCar estimate of £27,199.

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 1,805 priced BMW 4 Series adverts across different ages and specifications, as of 9 November 2026.

A 2021 BMW 4 Series with the 2.0 petrol engine is typically advertised at £24,000: the median of the 143 for sale on AskCar, as of 9 November 2026.

Time on sale

AskCar first saw this 2021 BMW 4 Series advertised 3 days ago. About 4 in 10 of 2021 BMW 4 Series cars are gone from sale within a month of being advertised: 111 of the 262 first advertised between 11 July 2026 and 6 October 2026.

Price history

AskCar first saw this advert on 6 November 2026 at £29,300. Its asking price is now £28,800, £500 less. The latest price cut was seen on 7 November 2026.

Price changes recorded:

• 6 November 2026: £29,300
• 7 November 2026: £28,800

Mileage and MOT

MOT, from the government's MOT records (DVSA, the Driver and Vehicle Standards Agency), as of 9 November 2026: valid until 21 October 2027.

It has had 3 MOTs. The latest, on 22 October 2026, passed.

There were no advisories at the latest test.

Mileage at that test: 17,141 miles, which matches the advertised 17,141 miles.

Advertised mileage is about 26,500 miles lower than the median mileage of a 2021 BMW 4 Series on AskCar.

Similar cars

24 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 9 November 2026.

The 3 closest to this car in mileage:

• 2021 BMW 4 Series M Sport, 2.0 petrol convertible, white. Mileage: 12,820 miles. Price: £27,691, £1,109 less than this car. Dealer: Hedin Automotive Enfield BMW in Enfield. AskCar page: https://askcar.co.uk/car/bmw-4-series-2021-5519f689856d
• 2021 BMW 4 Series M Sport, 2.0 petrol convertible, green. Mileage: 12,250 miles. Price: £33,950, £5,150 more than this car. Dealer: Kams Cars in Borehamwood. AskCar page: https://askcar.co.uk/car/bmw-4-series-2021-aea4aa4c4d93
• 2021 BMW 4 Series M Sport, 2.0 petrol convertible, black. Mileage: 22,399 miles. Price: £27,195, £1,605 less than this car. Dealer: John Clark BMW Tayside in Dundee. AskCar page: https://askcar.co.uk/car/bmw-4-series-2021-9751e81829b1

• The nearest: 2021 BMW 4 Series M Sport, 2.0 petrol convertible, white, 66 miles from this car. Mileage: 33,607 miles. Price: £24,850, £3,950 less than this car. Dealer: Evans Halshaw Vauxhall Newport in Newport. AskCar page: https://askcar.co.uk/car/bmw-4-series-2021-b45f7103a93e