The IRS has set the standard mileage rate for 2020 at 57.5 cents per mile. This is a decrease from 58 cents in 2019. Per the IRS announcement, “the standard mileage rate for business is based on an annual study of the fixed and variable costs of operating an automobile.” Employers are not required to pay the IRS mileage rate and can pay a higher or lower rate based on the actual costs for the employee using their vehicle.