In fiscal year 2024, the federal government spent a net total of $6.8 trillion. That money flowed through hundreds of agencies. Some operate independently, others sit within larger departments. These organizations take on responsibilities both large and small — from running major national programs such as Medicare or Social Security to inspecting food, managing forests, and delivering mail.

Most agencies submit annual funding requests, which the Office of Management and Budget (OMB) reviews. The president uses them to craft a proposed budget for the federal government. Congress then reviews and approves what money actually gets spent. Once the budget becomes law, the Treasury Department manages the flow of funds — collecting taxes, making payments, and tracking the results.

Not all programs go through this yearly process. Some, such as Social Security and Medicare, are funded automatically under laws that Congress has already passed. These are known as mandatory spending programs.

To understand how the federal budget works, it helps to look at the government’s structure. Most federal agencies fall under one of the three branches of government—executive, legislative, or judicial — each with its own role in shaping policy, managing operations, and using public funds.

The executive branch is responsible for carrying out the laws passed by Congress and oversees most of the federal government’s day-to-day operations. It also accounts for the vast majority of federal spending each year. In fiscal year 2024, nearly all of the $6.8 trillion in net federal spending flowed through executive agencies.

This branch includes three main components: the executive office of the president, cabinet-level departments, and independent agencies.

The executive office of the president (EOP) includes the president’s immediate staff and support offices. This includes the OMB, the National Security Council (NSC), and the Council of Economic Advisers. While not involved in directly administering federal programs, these offices play a key role in shaping policy, coordinating across agencies, and advising the president.

In 2024, the EOP accounted for a relatively small share of federal spending — around $1 billion or 0.01% of the budget.

These are the best-known agencies in the federal government, including the Defense Department, the Department of Health and Human Services (HHS), and the Treasury Department. Each is led by a Cabinet secretary appointed by the president and confirmed by the Senate. Cabinet departments are responsible for major areas of public policy, including transportation, agriculture, education, and the economy. They also help carry out the president’s priorities.

In 2024, HHS spent a net total of $1.7 trillion — about 25.4% of total federal spending, and more than any other Cabinet department. That total was driven almost entirely by the $1.5 trillion spent by the Centers for Medicare & Medicaid Services. Medicare and Medicaid are two of the largest mandatory spending programs in the federal budget.

Independent agencies are within the executive branch but operate separately from Cabinet departments. These include organizations such as the Social Security Administration, Environmental Protection Agency (EPA), and NASA.

Congress establishes these agencies and often tasks them with long-term responsibilities with some independence from presidential control. These include a range of missions from managing Social Security benefits or regulating environmental standards.

In 2024, the Social Security Administration accounted for the majority of independent agency spending: $1.5 trillion.

The judicial branch interprets the law and ensures the Constitution is upheld. It includes the Supreme Court of the United States, as well as appeals, district, and specialized courts.

In 2024, the judicial branch reported approximately $9.5 billion in net spending.

The legislative branch is responsible for making laws and overseeing the federal government’s operations. It includes both chambers of Congress — the House of Representatives and the Senate — as well as various support agencies including the Library of Congress, Congressional Budget Office, and Government Accountability Office.

Unlike executive branch agencies, the legislative branch does not administer large public programs. Instead, its spending supports the work of lawmakers, congressional staff, and the nonpartisan offices that analyze legislation and monitor government performance. In 2024, the legislative branch reported about $6.7 billion in net spending.

Not all government entities fit into one of the three branches. Some federal spending supports a mix of other agencies and quasi-official institutions that serve specialized roles.

Some of these are “other agencies” — relatively small departments created by Congress for specific purposes. Examples include the American Battle Monuments Commission, the Corporation for Travel Promotion, and the Patient-Centered Outcomes Research Trust Fund.

Others are considered quasi-official agencies. These include organizations like the Smithsonian Institution and the United States Holocaust Memorial Museum. Though established or supported by the federal government, many of these institutions also rely on private donations, ticket sales, and other non-government revenue.

In 2024, combined net spending for these “other” entities totaled roughly $5 billion.

Some government-related organizations don’t appear in this breakdown because they aren’t part of the Treasury Department’s federal budget report. This includes entities such as the Federal Reserve and government-sponsored enterprises such as Fannie Mae and Freddie Mac. While these organizations play important roles in the economy, they operate independently and are not funded through the regular federal budget process.