Yes. Tips for van drivers and other transportation expenses (train, taxi, bus, car rental) are all deductible separately from your meals and incidental expenses. Many per diem services (and even some CPAs) are confused by the terminology “incidental expenses”, and believe it to include all incidental expenses incurred during your layover. However, Section 300-3.1 of the Federal Travel Regulation specifically defines incidental expenses as only those pertaining to fees and tips given to porters, baggage carriers, hotel staff and staff on ships. The cost of transportation (including tips) between airports and places of lodging are not considered incidental expenses. The GSA also published interim regulations on September 7, 2011 that excluded transportation costs between places of lodging and places where meals are taken from inclusion in the Incidental portion of the M&IE rates. These costs may now also be claimed separately from, and in addition to, the standard meal allowance.