The second option is to claim deductions for vehicle expenses while performing qualified activities. To claim the standard mileage deduction, you must maintain a log of your qualifying miles.
Distance — enter the total distance in miles you traveled. If your report is for mileage from multiple days, attach a mileage log to your expense report as supporting documentation.
Instead, mileage can be claimed on line 9 for car and truck expenses ... If you're audited, the IRS will want to see a log that includes dates, destinations and the reasons for travel.
Other vehicle expenses and driving costs that aren ... you might require your employees to keep a manual mileage log for any business travel.‍ This logbook should include the trip's date ...