Direct Billing of car rental used for UTC business travel is a new service that World Travel provides. The process is the same as direct-billing airfare, and all trips involving direct-bill must have an approved Travel Request in IRIS. When renting vehicles in Chattanooga, a letter from Motor Pool stating no UT car is available must be attached to the T-25. We hope you will take advantage of this additional service from World Travel. The new T-25 form can be found on the Disbursements Home Page.