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: 36,250 miles
• Fuel: Diesel
• Body: Saloon, 4 doors, 5 seats
• Engine: 2.0 litres, 148 bhp
• Gearbox: Automatic (S tronic)
• Drive: Front-wheel drive
• Colour: Black
• CO2: 124 g/km
• Emissions standard: Euro 6, ULEZ compliant

About this car

This 2021 Audi A3 S Line has covered 36,250 miles, around 7,300 fewer miles than is typical for its age. Priced at £16,950, it is advertised £2,372 below the AskCar estimate of £19,322. To work out the AskCar estimate, we analyse UK dealer adverts for 6,542 Audi A3 cars across different ages and specifications. We first recorded this car for sale 2 days ago. Its advertised mileage matches the government's MOT record. The seller is Group 1 Automotive Watford Audi, based in Watford. 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

Good value: £2,372 (12%) under the AskCar estimate of £19,322.

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

AskCar first saw this 2021 Audi A3 advertised 2 days ago. About 6 in 10 of 2021 Audi A3 cars are gone from sale within a month of being advertised: 403 of the 709 first advertised between 7 July 2026 and 29 September 2026.

Price history

AskCar first saw this advert on 31 October 2026 at £16,950. 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 2 November 2026: valid until 15 January 2027.

It has had 4 MOTs. The latest, on 16 January 2026, passed.

There were no advisories at the latest test.

Mileage at that test: 31,378 miles, which matches the advertised 36,250 miles.

Advertised mileage is about 7,300 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 £18,950, as of 2 November 2026.

The 2 closest to this car in mileage:

• 2021 Audi A3 S Line, 2.0 diesel saloon, white. Mileage: 40,682 miles. Price: £18,950, £2,000 more than this car. Dealer: Group 1 Automotive Southend Audi in Thundersley and South Benfleet. AskCar page: https://askcar.co.uk/car/audi-a3-2021-9f7dbaa9cf1d
• 2021 Audi A3 S Line, 2.0 diesel saloon, grey. Mileage: 71,923 miles. Price: £15,995, £955 less than this car. Dealer: S & R Motors in Swindon. AskCar page: https://askcar.co.uk/car/audi-a3-2021-e7ef4cf5aa43