An executive agreement one of three mechanisms by which the United States enters into binding international agreements. They are considered treaties as the term is used under international law in that they bind both the United States and a foreign state. However, they are not considered treaties as the term is used under United States Constitutional law, because the United States Constitution's treaty procedure requires the advice and consent of two-thirds of the Senate, and these agreements are made solely by the President of the United States.

An executive agreement can only be negotiated and entered into through the president's authority (1) in foreign policy, (2) as commander-in-chief of the armed forces, or (3) from a prior act of Congress. For instance, it is as commander-in-chief that the President negotiates and enters into status of forces agreements (SOFAs), which govern the treatment and disposition of U.S. forces stationed in other nations. An executive agreement, however, cannot go beyond the President's constitutional powers. If an agreement was in the competence of the United States Congress, it would need to become a congressional-executive agreement or a treaty with Senate advice and consent. If an agreement was neither within the competence of Congress nor within the competence of the President (as for example an agreement which would affect powers reserved to the states), it could still be adopted by the President/Senate method but must not conflict with the United States Constitution. One should note that in contrast with many other nations (particularly in Europe), the United States does not consider international agreements to take precedence over domestic law.

Executive agreements are distinctly American and are a product of the Constitution. The Case Act requires the president to notify Congress of any executive agreements that are formed.

See also: Congressional-executive agreement