Background1

Trips by the President, Vice President, and First Lady are almost always classified as official travel or political travel, or a combination of the two. Official, or nonpolitical, travel is normally defined as anything having to do with the carrying out of presidential duties and responsibilities. Official travel may involve, for example, presenting information; giving direction; and explaining, and securing public support for, Administration policies. Political travel normally involves the President and Vice President in their positions as leaders of their political party. Attending party functions, participating in fundraising, and campaigning for candidates are examples of political activities. The terms are rather general, and the White House determines whether a trip is for official or political purposes, or for a combination of the two.
The travel policies of specific Administrations concerning the reimbursement of expenses for unofficial travel generally are not publicly available. However, the Reagan Administration established written guidelines in 1982 to determine when the President, Vice President, and any assistants accompanying them on military aircraft travel at government expense and when they, or the political organizations on whose behalf they travel, are to reimburse the government with the equivalent of the airfare that they would have had to pay had they traveled on commercial airlines. The guidelines evolved in response to general legal principles that federal funds are to be used only for the purposes for which they are appropriated, opinions from the Office of Legal Counsel in the Department of Justice, rules of the Federal Election Commission (FEC), and occasional audits by the General Accounting Office (GAO). The guidelines, which also cover the First Lady and the Vice President's spouse, apply only to trips in the United States and its territories, since all foreign travel is considered official. It appears likely that subsequent Administrations have used the Reagan Administration guidelines as a foundation for their own travel policies.

	Official and Unofficial Travel

When White House personnel are on official travel, certain personal expenses, which include per diem (food and lodging), car rentals, and other incidentals, are paid by the government. These expenses are paid by the White House for domestic travel, and by the State Department for foreign travel. Members of the President's staff and his immediate family, including the First Lady, are on official travel whenever their trips are designed to assist the President in discharging his duties and responsibilities. The same is true for members of the Vice President's staff and his immediate family. According to the Office of the Vice President, the Vice President's wife uses a military aircraft only when she accompanies him, or when she is designated as the Vice President's representative to attend a special function.
When travel is for political purposes, the President, Vice President, and First Lady, and any assistants accompanying them, are required to reimburse the government the comparable airfare they would have paid had they traveled by commercial airline. On such trips, they pay for their own food, lodging, and other incidental expenses. Certain staff accompanying them, however, such as Secret Service agents, are always considered to be on official travel, and all their travel costs are paid by the government.
When travel involves both official and political functions, the White House uses a formula to determine how much airfare is to be paid by the traveler, and how any per diem and other travel-related costs are to be paid by the government. For example, if the day is divided equally between an official and an unofficial event, then the President, Vice President, First Lady, and accompanying staff, or a political organization, must reimburse the government for 50% of the amount that would have been owed to the government if the entire trip had been political. A more detailed explanation is as follows:
In the instance of a mixed trip, the amount of the reimbursement for use of government aircraft will be prorated as indicated by the nature of the activity. Prorating the cost of air travel on mixed official/political trips may be accomplished through a formula based on the amount of time actually spent by the President and Vice President in meetings, receptions, rallies and similar activity. Time spent in actual travel, private study, or rest and recreation will not be included in the computation. The formula is as follows: Time spent in official meetings, receptions, etc. + Time spent in political meetings, receptions, rallies = Total activity time. Time spent in official activity ÷ Total activity time = Percentage of trip that is official. Time spent in political activity ÷ Total activity time = Percentage of trip that is political. The percentage figure that represents the political portion of the trip is then multiplied by the amount that would be reimbursed to the government if all of the travel was political. The product of that calculation represents the amount to be reimbursed to the government.
Other factors may result in adjustments to any amount of reimbursement. For example, if a traveling party would have returned to the point of departure on a given day, but delayed its return one day (or more) because of a political activity, then the cost of accommodations is to be assessed solely to the political sponsor. 
Sometimes it is difficult to determine whether a trip, or part of a trip, should be characterized as official or unofficial. This is especially the case when a trip involves certain activities having partisan consequences, because an inherent part of the official duties of the President and Vice President involves their efforts to present, explain, and secure public support for their policies and goals. When they travel and appear in public to defend their policy positions, the difference between their official duties and their activities as leaders of their political party can be difficult to assess. As a result, the White House decides the nature of travel on a case-by-case basis, attempting to determine whether each trip, or part of a trip, is or is not official by considering the nature of the event involved, and the role of the individual involved.
It is unclear how the White House designates travel that is not directly related to a governmental or political function, because of traditional reluctance to address this matter. It appears that, in most cases, such travel is treated as official, under the assumption that the President and Vice President are always on duty. Vacation trips, for example, fall under the official travel category.
Security considerations and the need to be able to communicate instantly with military and other officials at any time are the reasons the President flies on a military aircraft when he travels. Moreover, having a military plane readily available enables the President to fly whenever and wherever he may wish to go. Security considerations are also the primary reason for use of military aircraft by the Vice President and First Lady.

	Operational and Other Costs

Airfare and related travel expenses associated with the trips taken by the President, Vice President, and First Lady are only a fraction of the total cost of such trips. Most of the costs involve operational costs of the aircraft, and include fuel, maintenance, engineering support, and per diem expenses for the crew. The military aircraft used by the White House are operated by the 89 th Airlift Wing (AW) located at Andrews Air Force Base in Maryland, just outside Washington, DC. Among the aircraft in the 89 AW are two Boeing 747s (also known as VC-25As) that have been specially configured for the President's needs, and that are exclusively for his use. Electronic and communications equipment in the 747s enables the President to keep in touch at all times with civilian and military officials. The President flies on one of the 747s on most of his trips. Occasionally, he will use a smaller plane when the area he is visiting cannot accommodate a 747. "Air Force One" is the designation given to whatever plane the President is using at the time. Information provided by the U.S. Air Force in 2012 shows that the cost per hour for the President's 747 (which is designated "VC-25" by the Air Force) is $179,750. The Vice President and First Lady use aircraft different from the presidential 747. The Vice President primarily flies on a C-32; the First Lady primarily flies on a C-40 (the C-32 is an alternate).
Costs associated with these trips, however, generally involve much more than the operational costs of the specific passenger aircraft. When the President travels abroad, several passenger and cargo aircraft accompany Air Force One. When the Vice President or First Lady make such a trip, a single cargo aircraft accompanies either of them. On domestic trips, a cargo aircraft and a backup aircraft normally accompany only Air Force One. If the President is accompanied by more than 75 assistants and subordinates, including Secret Service staff, an additional passenger aircraft also makes the trip. Sometimes, an additional aircraft accompanies Air Force One to be available to take the President to a second city whose airport cannot accommodate a 747. Finally, in preparation for a trip, whether domestic or foreign, an advance party may make several trips to the destination or destinations that will be visited in order to assure that everything goes as planned.
Besides the maintenance and operational costs of the aircraft, there are the per diem and related costs mentioned earlier, when the trip is official, and the costs for those designated "official travelers" when the trip is not official. On a presidential trip, the number of these "official travelers" may be quite high, since it includes Secret Service agents, communications personnel, and various other officials.
Only recently has information become available regarding the overall cost associated with travel by the President, Vice President, and First Lady. In 1992, the House Committee on Post Office and Civil Service estimated that two presidential trips, one to Europe in 1989 and the other to Hawaii in 1990, cost the Air Force $1 million to $1.5 million, and that the average vice presidential trip cost the Air Force $250,000 to $500,000. These estimates involved operational costs; they did not include per diem and other travel-related expenses.
In 1999, GAO estimated the incremental costs, including per diem and related expenses, of presidential trips in 1998 to Africa, Chile, and China to be at least $42.8 million, $10.5 million, and $18.8 million respectively. In 2000, GAO estimated that the Department of Defense "spent at least $292 million to provide fixed-wing airlift and air refueling support for 159 White House foreign trips" (27 by the President, 20 by the First Lady, 8 by the Vice President, and 104 directed by the President) from January 1, 1997, through March 31, 2000. These estimates did not include per diem and other travel-related expenses.
Comparable information is not available regarding the cost of White House foreign (or domestic) trips for earlier or subsequent Administrations.

Summary:
For security and other reasons, the President, Vice President, and First Lady use military aircraft when they travel. The White House generally categorizes the trips as fulfilling either official or political functions. Often, a trip involves both official and political, or unofficial, activities. When a trip is for an official function, the government pays all costs, including per diem (food and lodging), car rentals, and other incidental expenses. When a trip is for political or unofficial purposes, those involved must pay for their own food and lodging and other related expenses, and they must also reimburse the government with the equivalent of the airfare that they would have paid had they used a commercial airline. When a trip involves both official and political activities, a formula determines the amount to be reimbursed for that part of the trip involving political activities. Whether a trip is for official or political purposes, the Air Force pays all operational and other costs incurred by the use of the aircraft. While the travel policies of specific Administrations concerning the reimbursement of expenses for unofficial travel generally are not publicly available, it appears that policy guidelines developed by the Reagan White House have served as a basis for the travel policies of subsequent Administrations. This report will be updated as new information becomes available.