You can only deduct the cost of a vehicle on your tax return if it is used in a business that you own. You will see a section for Business Vehicle Expenses when you enter your business income and expenses. You must complete that section to determine what deduction options you have for the vehicle. Your deduction will depend on a variety of factors, such as the type and size of the vehicle, the percentage of business use versus personal use, the income of the business and other considerations.