How the federal government is organized, and how it spends.

The three branches, in one paragraph each

The legislative branch is Congress: the House of Representatives and the Senate. It writes the laws, and it holds the power of the purse. No federal dollar is spent unless Congress authorizes it, through authorizing laws that create programs and appropriations bills that fund them each year.

The executive branch is the President, the 15 departments, and the agencies. It does the spending: it hires the workforce, signs the contracts, issues the grants, and pays the benefits that Congress authorized. Almost every dollar traced on this site leaves the Treasury through an executive branch agency.

The judicial branch is the Supreme Court and the lower federal courts. It interprets the law and settles disputes. It is the smallest spender of the three by far, and its financial disclosures are the newest public system (see the disclosures guide).

The money loop is simple: Congress appropriates, the executive spends, and the Treasury’s Fiscal Service moves the money through the Treasury General Account at the Federal Reserve Bank of New York.

The 15 executive departments

In presidential succession order. Department heads are nominated by the President and confirmed by the Senate. The Cabinet is the Vice President, the 15 department heads, and other officials the President designates (commonly the White House Chief of Staff, the EPA Administrator, the OMB Director, the U.S. Trade Representative, the UN Ambassador, the CEA Chair, and the SBA Administrator).

Beyond the departments: the independent agencies

Several major agencies sit outside the 15 departments and rival them in budget size. The Social Security Administration paid about $1,368 billion fiscal year to date through July 2025 (Monthly Treasury Statement), making it one of the largest spenders in government. Others include the Environmental Protection Agency, NASA, the Small Business Administration, and the Office of Personnel Management.

How departments spend: the channel lens

Every department moves money through a small set of channels. Personnel covers military and civilian payroll. Operations covers running costs: fuel, facilities, maintenance. Procurement buys weapons systems, IT, and equipment. Research and development funds science and technology. Benefits are direct payments to individuals, mostly mandatory. Grants flow to states, localities, universities, and nonprofits. Contracts buy goods and services from the private sector. Interest services the debt.

Each department has a signature mix. Ask what share is checks to people, what share is payroll, and what share is buying things, and the department’s character emerges:

• HHS (through CMS) and VA (through VBA) are benefits-heavy. Most of their money is payments to people.
• Defense is personnel, operations, and procurement heavy. Paychecks, fuel, maintenance, and weapons.
• HHS (through NIH and ACF), Education, and Transportation are grant-heavy. Research grants, student aid, and highway funds flow outward to states and institutions.
• Treasury is interest-heavy. Servicing the debt dwarfs its operating bureaus.
• DHS and Justice are personnel and operations heavy, with large law-enforcement components.

Mandatory vs. discretionary: why some budgets can be cut and others cannot

Mandatory spending is set by authorizing law: programs like Medicare, Social Security, and veterans benefits pay out according to eligibility rules, not annual votes. Discretionary spending is set each year through appropriations: defense operations, NIH research, and agency payroll are all decided annually.

The mix varies wildly by department. VA is roughly two-thirds mandatory. HHS is overwhelmingly mandatory through Medicare and Medicaid. Defense is almost entirely discretionary. That is why a single “cut the budget” conversation means completely different things at different departments.

The workforce, as a spending lens

Vintage: OPM Federal Workforce Data, launched January 2026; GAO accounting of CFO Act agencies, December 2024 to January 2026. Figures are reported as published; the Ledger takes no position on the policy behind them.

Payroll is the most intuitive spending category. OPM reports about 2,084,618 civilian employees currently serving, with 86.6 percent working outside the DC area and an average salary of $110,744. A GAO accounting of CFO Act agencies found the largest civilian workforces at Defense (778,188 in December 2024), Veterans Affairs (480,075), Homeland Security (231,337), Justice (117,379), Treasury (117,063), HHS (93,035), and Agriculture (91,047). Total CFO Act agency civilian employment fell from 2,268,585 to 2,012,614 over that period, an 11.3 percent decline.

One caution: headcount and spending do not move together. Education has one of the smallest workforces and one of the largest grant flows. VA has a huge workforce because it runs hospitals. Personnel is one channel among many.

Travel and the charge card

Vintage: FY2025, GSA SmartPay program; April 2026 GSA release on the GO.gov system.

Government travel is publicly tracked through GSA’s SmartPay charge card program: $39.4 billion across 82 million transactions in FY2025, with $471 million in refunds, across 250 agencies. Cumulative government-wide travel spend runs about $35 billion. A new government-wide travel system called GO.gov (IBM, 15-year contract) launches in November 2026, projected to save up to $131 million per year.

Glossary

Department profiles

Deep dives on the departments with fully verified figures, each with its spending breakdown and vintage labels.

More department profiles are added as figures are verified. See also the public officials’ financial disclosures guide, which explains how to look up the stock trades, travel, and gifts reported by federal officials.

Sources

• Department missions and Cabinet composition: archived White House cabinet page (structure unchanged)
• FY2025 NDAA totals and splits: CRS IN12404
• HHS FY2025 budget request: CRS R48060
• VA FY2025 enacted appropriations: CRS R48608
• Treasury FY2025 appropriations: CRS R48188
• Monthly Treasury Statement, July 2025 (SSA and Treasury outlays): fiscal.treasury.gov
• Federal workforce data: OPM Federal Workforce Data launch coverage; GAO workforce accounting
• USAspending.gov (contract, grant, and award detail): usaspending.gov