The 2021 BMW X3 is available as a 4-door, 5-seat sport utility. Starting at $45,000, the 2021 BMW X3 xDrive30i AWD is powered by a 2.0L, 4-cylinder engine mated to an automatic transmission that returns an EPA estimated 23-mpg in the city and 29-mpg on the highway. The top of the line 2021 BMW X3 4x2, priced at $43,000, is powered by a 2.0L, 4-cylinder engine mated to an automatic transmission that returns an EPA estimated 25-mpg in the city and 29-mpg on the highway.