2021 Audi A3 2.0 TDI S Line

Overview

• Make: Audi
• Model: A3
• Trim: S Line
• Version: 2.0 TDI 35 S Line S tronic FWD Euro 6 (s/s) 4dr (148 bhp)
• Year: 2021
• Mileage: 40,682 miles
• Fuel: Diesel
• Body: Saloon, 4 doors, 5 seats
• Engine: 2.0 litres, 148 bhp
• Gearbox: Automatic (S tronic)
• Drive: Front-wheel drive
• Colour: White
• CO2: 124 g/km
• Emissions standard: Euro 6, ULEZ compliant

About this car

With 40,682 miles on the clock, this 2021 Audi A3 S Line has done roughly 2,900 fewer miles than a typical 2021 Audi A3. Priced at £18,950, it is advertised £83 above the AskCar estimate of £18,867. To work out the AskCar estimate, we analyse UK dealer adverts for 6,542 Audi A3 cars across different ages and specifications. This car was first seen in our listings data 23 days ago. According to the government's MOT record, its advertised mileage is consistent with the latest test. The seller is Group 1 Automotive Southend Audi, based in Southend. How to contact the dealer and its opening hours are on this AskCar page.

Stock data as of 2 November 2026.

How we estimate prices and check cars

Price

Fair price: £83 (under 1%) over the AskCar estimate of £18,867.

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 6,542 priced Audi A3 adverts across different ages and specifications, as of 2 November 2026.

A 2021 Audi A3 with the 2.0 diesel engine is typically advertised at £17,400: the median of the 45 for sale on AskCar, as of 2 November 2026.

Time on sale

This 2021 Audi A3 has been on sale for at least 23 days.

Price history

AskCar first saw this advert on 10 October 2026 at £18,795. Its asking price is now £18,950, £155 more.

Price changes recorded:

• 10 October 2026: £18,795
• 20 October 2026: £18,450
• 25 October 2026: £18,795
• 29 October 2026: £18,950

Mileage and MOT

MOT, from the government's MOT records (DVSA, the Driver and Vehicle Standards Agency), as of 2 November 2026: valid until 26 October 2027.

It has had 5 MOTs. The latest, on 13 October 2026, passed.

There were no advisories at the latest test.

Mileage at that test: 40,681 miles, which matches the advertised 40,682 miles.

Advertised mileage is about 2,900 miles lower than the median mileage of a 2021 Audi A3 on AskCar.

Similar cars

2 other 2021 Audi A3 S Line 2.0 diesel automatic saloons are for sale at UK dealers, from £15,995 to £16,950, as of 2 November 2026.

The 2 closest to this car in mileage:

• 2021 Audi A3 S Line, 2.0 diesel saloon, black. Mileage: 36,250 miles. Price: £16,950, £2,000 less than this car. Dealer: Group 1 Automotive Watford Audi in Watford. AskCar page: https://askcar.co.uk/car/audi-a3-2021-c91e9540ac3c
• 2021 Audi A3 S Line, 2.0 diesel saloon, grey. Mileage: 71,923 miles. Price: £15,995, £2,955 less than this car. Dealer: S & R Motors in Swindon. AskCar page: https://askcar.co.uk/car/audi-a3-2021-e7ef4cf5aa43