5 U.S.C § 5702 gives the Administrator of the U.S. General Services Administration (GSA) the authority to establish the system of reimbursing Federal employees for the subsistence expenses (lodging, meals, and incidentals) of official travel. The law governs how GSA sets rates today, and allows the GSA Administrator to establish locality-based allowances for these expenses with a reporting requirement back to Congress. The law was established to protect Federal employees by fairly reimbursing them for travel expenses. In addition, if a Federal employee cannot find a room within the established per diem rates, the travel policy allows the agency to reimburse the actual hotel charges up to 300 percent of the established per diem rates.
The per diem program has several standards that it follows in its systematic structured per diem methodology. The first level is having a “standard rate” that applies to approximately 85 percent of counties in the continental United States.
It is GSA’s policy that, if and when a Federal agency, on behalf of its employees, requests that the standard rate is not adequate in a specific area to cover costs of travel as intended by the law, GSA will study the locality to determine whether the locality under study should become a “non-standard area.” If the study recommends a change, a change will be implemented as deemed appropriate. GSA has implemented a process to review and update both the standard and non-standard areas annually.
The standard “boundary line” for where non-standard areas apply is generally one county. This is the case for approximately 85 percent of the non-standard rates that GSA sets. However, in some cases, agencies have requested that the rate apply to an area larger than one county, such as a metropolitan area. In a very small number of cases, an agency can and has requested that a rate apply to just a city and not the entire county. In some rural areas, a rate sometimes applies to more than one county due to lack of an adequate data sample to set a rate otherwise.
GSA uses the Federal Information Processing Series (FIPS) code standard for its apply areas. While GSA often uses ZIP codes to select hotel data samples, the apply area is coded by a FIPS code, unless a Federal agency only wants the rate to apply to certain ZIP codes. These codes are managed by the American National Standards Institute (ANSI) to ensure uniform identification of geographic entities through all federal government agencies.