The federal government of the United States is the centralized United States governmental body established by the Constitution. The federal government has three branches: the legislative, executive, and judicial. Through a system of separation of powers or "checks and balances," (inspired by the work of the Enlightenment philosopher Montesquieu) each of these branches has some authority to act on its own, some authority to regulate the other two branches, and has some of its own authority, in turn, regulated by the other branches. In addition, the powers of the federal government as a whole are limited by the Constitution, which leaves a great deal of authority to the individual states.

The seat of the federal government is in the federal district of Washington, D.C., often referred to metonymically as "Washington".