Why Some Federal Agencies Never Close During a Shutdown
A government shutdown doesn't switch off the federal government. It switches off only the parts Congress funds one year at a time.
The mail still comes during a government shutdown. Social Security checks still go out. Air traffic controllers still show up. But a National Park visitor center goes dark, a farm loan office stops answering the phone, and a federal employee two floors up might be told not to come in at all, sometimes within three to four hours of the funding lapse taking effect. None of that is random. It's the direct result of how, and whether, Congress funded that particular office.
\n\nWhy Do Some Agencies Stay Open During a Shutdown?
\nA shutdown happens when Congress hasn't passed either a full-year spending bill or a stopgap continuing resolution for a given agency by the time its funding expires. The Bipartisan Policy Center notes that Article I of the Constitution and the 19th-century Antideficiency Act together bar federal agencies from spending money Congress hasn't appropriated. But that rule only touches discretionary spending, the roughly quarter of the federal budget Congress approves year to year through 12 separate appropriations bills. Mandatory programs like Social Security and Medicare, which make up about 60% of federal spending, keep running because Congress authorized them to spend without an annual renewal. Interest payments on the national debt, about 15% of spending, are untouched for the same reason.
\n\nSome agencies clear the bar a different way entirely: they aren't funded by annual appropriations at all. Government-contracting consultancy Winvale points to the General Services Administration, which runs on an Industrial Funding Fee collected from contractors rather than a line in the federal budget, and the U.S. Postal Service, which is funded by stamp and package revenue and keeps operating as an essential government service regardless of what Congress does. That self-funded status is also why Congress had to change the law rather than the budget when it wanted to cap how often USPS could raise stamp prices.
\n\nWho Decides What Counts as Essential?
\nEach agency writes its own shutdown contingency plan, reviewed by the Office of Management and Budget, sorting employees into two buckets: "excepted," meaning their work protects life or property and continues under emergency rules, and "exempt," meaning they're paid from a source outside the annual appropriations fight. Everyone else gets furloughed. That's why the split looks different every time; the plans get updated every few years, and which activities make the essential list can shift with the administration in charge.
\n\nUnder that framework, the Federal Aviation Administration keeps its air traffic controllers at their stations, the Coast Guard and Customs and Border Protection stay on the job at Homeland Security, active-duty military personnel report as normal, and the Bureau of Land Management keeps processing oil and gas permits, while at the very same department, National Park visitor centers and landmarks close. The FDA, Medicare and Medicaid keep functioning inside Health and Human Services because they draw on mandatory funding, and the IRS has leaned on a dedicated funding stream enacted in 2022 to stay open during recent lapses. NASA keeps the space station running. State Department embassies keep issuing passports and visas.
\n\n\n\nWhy Doesn't This Just End the Fight Over Funding?
\nBecause the agencies that do close are neither small nor symbolic. The most recent Homeland Security funding lapse ran 75 days, from February 14 through April 30, 2026, the longest partial shutdown in U.S. history, according to the Bipartisan Policy Center, and the 2025 government-wide shutdown before it furloughed about 670,000 federal employees while another 730,000 kept working without pay until it ended. The Congressional Budget Office projected that shutdown would cost the economy $11 billion in lost growth by the end of 2026 if it ran six weeks; it ran 43 days. More than 1,000 TSA workers quit during the 2026 Homeland Security lapse alone, according to reporting cited by the Bipartisan Policy Center, thinning a workforce that doesn't get back pay until funding resumes.
\n\nDaybreak Wire has covered how Congress keeps beating shutdown deadlines with continuing resolutions without ever passing a real budget, and this is the flip side of that same habit. A CR buys time; it doesn't decide which agencies get multi-year funding, mandatory status or a fee-based revenue stream that insulates them from the next fight. The agencies that stay open in a lapse are, structurally, the ones already built not to need this year's fight resolved on time.
\n\nWhat Happens to the Agencies That Do Close?
\nEveryone else, the roughly three-quarters of government funded on the annual cycle, either furloughs non-excepted staff or keeps essential employees working unpaid until Congress acts. Contracts freeze; no new ones get signed. Small businesses feel it twice: first through halted federal contracts (nearly $184 billion went to small businesses in fiscal 2024, close to 29% of all contract dollars), and again if they need a Small Business Administration loan while SBA's own lending function is disrupted. Missed paychecks ripple into local economies well beyond the federal workforce itself, and credit ratings agencies have warned that repeated shutdowns make investors nervous enough about U.S. fiscal management to demand a higher return on U.S. debt.
\n\nThe mail keeps coming either way. That's less a comment on the Postal Service's importance than on how differently Congress decided, years ago and largely by accident of funding structure, to insulate one agency from a fight it still lets consume most of the rest of the government on a schedule.
