The travel allowance (also known as per diem or GSA rates) is the set amount a traveler is reimbursed for lodging, meals, and incidental expenses. You have to add the travel allowance to your reimbursement /expense report to be reimbursed for these expenses. The GSA rate for lodging and meals varies based on your travel location. While Concur will automatically calculate this for you, you can also look up the rates on the GSA website under the "Current Federal Fiscal Year."