If the Mileage Allowances was paid as actual travelling for the company business, the allowance will not be taxable income of the staff. However the company must be aware that the non-taxable mileage allowance rate should not be over the rule of “Ministry of Finance Governing the reimbursement of expenses for official travel” which is 4 Baht per Kilometer. For the exceeding amount of 4 Baht/Km. will be subjected to WHT (personal income tax) under the Revenue Code .
However, in normal practice the most company is willing to take risk on the under WHT deduction of staff taxable income in case they provide more than 4 Baht/Km. for staff travelling.