The 2021 Audi A4 is available as a 4-door, 5-seat sedan. Starting at $39,100, the 2021 Audi A4 40 is powered by a 2.0L, 4-cylinder engine mated to an automatic transmission that returns an EPA estimated 24-mpg in the city and 31-mpg on the highway. The top of the line 2021 Audi A4 45, priced at $40,900, is powered by a 2.0L, 4-cylinder engine mated to an automatic transmission that returns an EPA estimated 24-mpg in the city and 31-mpg on the highway.