2021 Audi A4 Avant 2.0 TDI S Line

Overview

• Make: Audi
• Model: A4 Avant
• Trim: S Line
• Version: 2.0 TDI S Line S tronic FWD Euro 6 5dr (160 bhp)
• Year: 2021
• Mileage: 18,925 miles
• Fuel: Diesel, mild hybrid
• Body: Estate, 5 doors, 5 seats
• Engine: 2.0 litres, 160 bhp
• Gearbox: Automatic (S tronic)
• Drive: Front-wheel drive
• Colour: Grey
• CO2: 142 g/km
• Emissions standard: Euro 6, ULEZ compliant

About this car

With 18,925 miles on the clock, this 2021 Audi A4 Avant S Line has done roughly 40,800 fewer miles than a typical 2021 Audi A4 Avant. The dealer is asking £22,000, which is £1,205 below the AskCar estimate of £23,205. To work out the AskCar estimate, we analyse UK dealer adverts for 1,232 Audi A4 Avant cars across different ages and specifications. We first recorded this car for sale 5 days ago. Its advertised mileage matches the government's MOT record. The seller is Car Planet Watford, based in Rickmansworth. 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: £1,205 (5%) under the AskCar estimate of £23,205.

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 1,232 priced Audi A4 Avant adverts across different ages and specifications, as of 4 November 2026.

A 2021 Audi A4 Avant with the 2.0 diesel engine is typically advertised at £18,500: the median of the 95 for sale on AskCar, as of 4 November 2026.

Time on sale

AskCar first saw this 2021 Audi A4 Avant advertised 5 days ago. About 4 in 10 of 2021 Audi A4 Avant cars are gone from sale within a month of being advertised: 48 of the 109 first advertised between 11 July 2026 and 1 October 2026.

Price history

AskCar first saw this advert on 30 October 2026 at £22,000. 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 one MOT, on 30 June 2026, and passed.

There were no advisories at the latest test.

Mileage at that test: 18,845 miles, which matches the advertised 18,925 miles.

Advertised mileage is about 40,800 miles lower than the median mileage of a 2021 Audi A4 Avant on AskCar.

Similar cars

18 other 2021 Audi A4 Avant S Line 2.0 diesel automatic estates are for sale at UK dealers, from £8,999 to £22,000, as of 4 November 2026.

The 3 closest to this car in mileage:

• 2021 Audi A4 Avant S Line, 2.0 diesel estate, blue. Mileage: 31,041 miles. Price: £19,780, £2,220 less than this car. Dealer: Carsa Cannock in Cannock. AskCar page: https://askcar.co.uk/car/audi-a4-avant-2021-0ba1228a6b50
• 2021 Audi A4 Avant S Line, 2.0 diesel estate, blue. Mileage: 35,650 miles. Price: £20,995, £1,005 less than this car. Dealer: Rodden Road Cars in Frome. AskCar page: https://askcar.co.uk/car/audi-a4-avant-2021-a059a41f72c2
• 2021 Audi A4 Avant S Line, 2.0 diesel estate, black. Mileage: 37,348 miles. Price: £22,000, the same price as this car. Dealer: Sytner Group Nottingham Audi in Nottingham. AskCar page: https://askcar.co.uk/car/audi-a4-avant-2021-fdc420d540c4

• The nearest: 2021 Audi A4 Avant S Line, 2.0 diesel estate, black, 32 miles from this car. Mileage: 42,000 miles. Price: £20,290, £1,710 less than this car. Dealer: Stratus in Basingstoke. AskCar page: https://askcar.co.uk/car/audi-a4-avant-2021-5c4e0c48c174