The 2021 BMW X4 is available as a 4-door, 5-seat sport utility. Starting at $51,600, the 2021 BMW X4 xDrive30i is powered by a 2.0LL , 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 2021BMWX4M40i , priced at $ 61,700 , is powered by a 3.0LL , 6 - cylinder engine mated to an automatic transmission that returns an EPA estimated 21-mpg in the city and 27-mpg on the highway.