2021 BMW 4 Series

2.0 420i M Sport Auto RWD Euro 6 (s/s) 2dr (181 bhp)

£18,990

Above the going rate: £2,350 over the typical £16,640 for this model, age and mileage, drawing on 1,749 adverts of this make and model.

Overview

Make: BMW
Model: 4 Series
Trim: M SPORT
Version: 2.0 420i M Sport Auto RWD Euro 6 (s/s) 2dr (181 bhp)
Mileage: 97,313 miles
Year: 2021
Fuel type: Petrol
Body type: Convertible
Engine: 2.0 L
Gearbox: Automatic
Power: 181 bhp
Seats: 4
CO2: 160 g/km
Colour: Blue
Doors: 2
Driven wheels: Rear Wheel Drive
Engine badge: 420i
Emissions standard: Euro 6

About this car

This 2021 BMW 4 Series M Sport is advertised with 97,313 miles on the clock. Our estimated market asking price is £16,640. This car is advertised at £18,990, which is £2,350 above that figure. To estimate its market asking price, we analyse UK dealer adverts for 1,749 BMW 4 Series cars across different ages and specifications. Since we first spotted the advert 72 days ago, the asking price has dropped by £3,000. The latest MOT recorded 97,921 miles, above the advertised mileage. Check this with the dealer. It is for sale at CS Autos Prestige Cars in Runnymede.

Stock data from 21 October 2026.

How we estimate prices and check cars

Price history

First seen on 11 August 2026, 72 days ago. Advert duration calculated on 22 October 2026. Net asking-price reduction: £3,000 from the first recorded £21,990. 1 price reduction recorded, the latest observed on 16 October 2026.

Recorded asking prices
Date observed	Asking price
11 August 2026	£21,990
16 October 2026	£18,990
21 October 2026	£18,990

Price and mileage comparison

Estimated market asking price: £16,640. The asking price is £2,350 above this estimate.

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

The pricing calculation includes 1,749 adverts of this make and model across different ages and specifications.

Advertised mileage is approximately 55,300 miles higher than typical for a 2021 BMW 4 Series.

Mileage concern: the advertised mileage is below the last MOT reading; ask the dealer to explain.

86 other cars with the same year, trim, gearbox and fuel are for sale from £16,995 to £41,000.

Other matching cars (up to five, cheapest first)
Asking price	Mileage
£16,995	96,000 miles
£17,490	56,431 miles
£19,900	77,199 miles
£20,750	86,002 miles
£20,950	70,584 miles

Matching year, trim, gearbox and fuel does not mean matching mileage or every specification. Our estimate adjusts for these differences using the wider market data.

Browse all BMW 4 Series cars for sale · 2021 BMW 4 Series price guide

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Dealer

CS Autos Prestige Cars, Runnymede. Across the dealer network: 28 cars for sale.

Dealer postcode: KT15 1ET.