2021 Audi A3 1.5 TFSI S Line

Overview

• Make: Audi
• Model: A3
• Trim: S Line
• Version: 1.5 TFSI 35 S Line S tronic FWD Euro 6 (s/s) 4dr (148 bhp)
• Year: 2021
• Mileage: 51,176 miles
• Fuel: Petrol, mild hybrid
• Body: Saloon, 4 doors, 5 seats
• Engine: 1.5 litres, 148 bhp
• Gearbox: Automatic (S tronic)
• Drive: Front-wheel drive
• Colour: Black
• CO2: 131 g/km
• Emissions standard: Euro 6, ULEZ compliant

About this car

This 2021 Audi A3 S Line has covered 51,176 miles, around 7,600 more miles than is typical for its age. Priced at £17,495, it is advertised £39 above the AskCar estimate of £17,456. To work out the AskCar estimate, we analyse UK dealer adverts for 6,542 Audi A3 cars across different ages and specifications. It first appeared in our advert records 20 days ago. According to the government's MOT record, its advertised mileage is consistent with the latest test. It is for sale at NSA Motor Vehicles in Milton Keynes. 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: £39 (under 1%) over the AskCar estimate of £17,456.

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 1.5 petrol engine is typically advertised at £18,000: the median of the 191 for sale on AskCar, as of 2 November 2026.

Time on sale

This 2021 Audi A3 has been on sale for at least 20 days.

Price history

AskCar first saw this advert on 13 October 2026 at £17,495. 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 30 March 2027.

It failed its MOT on 31 March 2026 (offside rear shock absorbers has a serious fluid leak) and passed later the same day.

There were no advisories at the latest test.

Mileage at that test: 46,624 miles, which matches the advertised 51,176 miles.

Advertised mileage is about 7,600 miles higher than the median mileage of a 2021 Audi A3 on AskCar.

Similar cars

31 other 2021 Audi A3 S Line 1.5 petrol automatic saloons are for sale at UK dealers, from £11,995 to £20,995, as of 2 November 2026.

The 3 closest to this car in mileage:

• 2021 Audi A3 S Line, 1.5 petrol saloon, black. Mileage: 50,342 miles. Price: £18,150, £655 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-ebf6ec9bf222
• 2021 Audi A3 S Line, 1.5 petrol saloon, grey. Mileage: 53,412 miles. Price: £17,250, £245 less than this car. Dealer: Vertu Honda Stockton in Stockton-on-Tees. AskCar page: https://askcar.co.uk/car/audi-a3-2021-cd7c671bba5d
• 2021 Audi A3 S Line, 1.5 petrol saloon, black. Mileage: 55,000 miles. Price: £17,304, £191 less than this car. Dealer: Shepshed Ford in Shepshed. AskCar page: https://askcar.co.uk/car/audi-a3-2021-eae480dfac43

• The nearest: 2021 Audi A3 S Line, 1.5 petrol saloon, black, 5 miles from this car. Mileage: 36,644 miles. Price: £18,180, £685 more than this car. Dealer: Evans Halshaw BYD Milton Keynes in Milton Keynes. AskCar page: https://askcar.co.uk/car/audi-a3-2021-591d7c0e70ce