Mileage is an allowable deduction if you’re self-employed or own your own business. You can choose between the standard mileage rate or the actual cost method where you keep track of what you paid for gas and maintenance.
To use the standard mileage rate, you must keep a log of each trip with miles driven during the first year your vehicle is used for business. After that, you can either go with standard mileage or actual cost (unless you lease, in which case you must stick with standard mileage for the duration of the lease). However, if you use the actual cost method in the first year the vehicle is used for business, you must always use the actual cost method.
If you're using the standard mileage rate, you must keep a log that shows the date, business purpose of each trip, and miles driven. The standard mileage rate includes allowances for fuel, insurance, maintenance, repairs, and wear and tear. The only additional vehicle expenses you can deduct on top of the standard mileage rate are parking fees and highway tolls.
Taxpayers can also claim mileage for medical or charitable purposes, and active-duty military can claim mileage for the move to a permanent change of station (PCS) under military orders.
Employees can no longer deduct work-related mileage in tax years 2018 through 2025 due to the Tax Cuts and Jobs Act (TCJA) that Congress signed into law on December 22, 2017. Prior to the tax law change, employees could deduct mileage for commuting between multiple job sites during the same day, as well as commutes to temporary work locations and offsite business meetings.