Business travel deductions are available when employees must travel away from their tax home or main place of work for business reasons. Travel expenses ARE a necessity of doing business but there are ways to save and reduce.This guide takes the top corporate travel expense questions and answers them for you. To establish the Travel and Employee Expense Reimbursement. Travel expenses are costs incurred while traveling specifically for the purpose of conducting business-related activities. Travel expense reimbursement is when an employer reimburses its employees for business travel expenses. A business travel expense is a cost incurred when traveling for business purposes. This can include the cost of products or services necessary for the trip. The IRS's general rule of thumb can be summed up in two words: "ordinary and necessary. Your business has to track every travel expense for tax purposes.