2021 Audi A3 2.0 TDI S Line
Version: 2.0 TDI 35 S Line S tronic FWD Euro 6 (s/s) 4dr (148 bhp)
Price: £16,950. Good value: £2,116 (11%) under the AskCar estimate of £19,066, our expected asking price for this car from its model, age, mileage and specification, drawing on 6,600 priced Audi A3 adverts on AskCar as of 31 October 2026.
AskCar lists 6,729 used Audi A3 from 2,260 UK dealerships, as of 31 October 2026.
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)
- Mileage
- 36,250 miles
- Year
- 2021
- Fuel type
- Diesel
- Body type
- Saloon
- Engine
- 2.0 L
- Gearbox
- Automatic
- Power
- 148 bhp
- Seats
- 5
- CO2
- 124 g/km
- Colour
- Black
- Doors
- 4
- Driven wheels
- Front Wheel Drive
- Gearbox version
- S tronic
- Engine badge
- TDI
- Emissions standard
- Euro 6
About this car
This 2021 Audi A3 S Line has covered 36,250 miles, around 7,100 fewer miles than is typical for its age. Priced at £16,950, it is advertised £2,116 below the AskCar estimate of £19,066. To work out the AskCar estimate, we analyse UK dealer adverts for 6,600 Audi A3 cars across different ages and specifications. We have tracked this advert today. Its recorded MOT is valid until 15 January 2027, and its advertised mileage is consistent with the latest MOT reading. The seller is Group 1 Automotive Watford Audi, based in Watford.
Stock data as of 31 October 2026.
Price history
AskCar first saw this advert on 31 October 2026.
| Date observed | Asking price |
|---|---|
| 31 October 2026 | £16,950 |
Price and mileage comparison
Good value: £2,116 (11%) under the AskCar estimate of £19,066.
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 6,600 priced Audi A3 adverts across different ages and specifications, as of 31 October 2026.
Advertised mileage is about 7,100 miles lower than the median mileage of a 2021 Audi A3 on AskCar.
The advertised mileage is consistent with the last MOT reading.
MOT
MOT: valid until 15 January 2027. 31,378 miles at the last test.
Other matching cars
10 other 2021 Audi A3 S Line automatic diesel cars are for sale at UK dealers from £15,650 to £18,950, as of 31 October 2026.
The 5 cheapest:
- 2021 Audi A3. Price: £15,650. Mileage: 63,113 miles. Dealer: Stoneacre in Peterborough. AskCar page: https://askcar.co.uk/car/audi-a3-2021-fad3c596abe9
- 2021 Audi A3. Price: £15,950. Mileage: 93,000 miles. Dealer: MC Autosales in Magherafelt. AskCar page: https://askcar.co.uk/car/audi-a3-2021-60423bfb94a1
- 2021 Audi A3. Price: £15,995. Mileage: 71,923 miles. Dealer: S & R Motors in Swindon. AskCar page: https://askcar.co.uk/car/audi-a3-2021-e7ef4cf5aa43
- 2021 Audi A3. Price: £16,550. Mileage: 50,311 miles. Dealer: Big Motoring World Blue Bell Hill in Blue Bell Hill. AskCar page: https://askcar.co.uk/car/audi-a3-2021-b7a4c48f1a83
- 2021 Audi A3. Price: £17,400. Mileage: 45,833 miles. Dealer: Essex Car Company in Rainham. AskCar page: https://askcar.co.uk/car/audi-a3-2021-05a9f027fafc
The 10 matching cars have covered 25,000 to 93,000 miles, compared with 36,250 miles for this car.
Matching year, trim, gearbox and fuel does not mean matching mileage or every specification. The AskCar estimate adjusts for these differences.
Browse all Audi A3 cars for sale · 2021 Audi A3 price guide
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Photos
1 photo of this car is on its AskCar page.
How to contact the dealer and its opening hours are on this AskCar page.
As of 31 October 2026, AskCar lists 583,548 cars and vans from 12,716 UK dealerships, read daily from dealer websites: over 99% of UK dealer used car adverts. No dealer pays to be listed.