On September 25, 2023, the IRS announced the special per diem rates effective October 1, 2023, which taxpayers may use to substantiate the amount of expenses for lodging, meals, and incidental expenses when traveling away from home. Notice 2023-68 provides the special transportation industry rate, the rate for the incidental expenses only deduction, and the rates and list of high-cost localities for purposes of the high-low substantiation method. Further, Rev. Proc. 2019-48 provides the rules for using per diem rates, rather than actual expenses, to substantiate the amount of expenses for lodging, meals, and incidental expenses for travel away from home.