Per Diem in Lieu of Actual Subsistence Incident to Temporary Duty

An advance decision was requested regarding determination of the amount of per diem in lieu of subsistence due an employee incident to a temporary duty assignment. The employee may not be paid the maximum per diem under the lodging-plus method based on a receipt for lodgings provided in his mother-in-law's home even though that amount equaled the cost of the least expensive commercial facilities available since payment of lodging costs to relatives based on commercial rates is not reasonable. The agency may not establish a specific per diem rate in this situation since such rate was established in advance as required by applicable regulations.