The United States government’s fiscal year ends on Sept. 30, and if Congress doesn’t allocate funding to all 438 government agencies, “large swaths of the U.S. government could temporarily close on Oct. 1,” per Reuters.

Why do shutdowns happen?

The U.S. Constitution says, “No money shall be drawn from the Treasury, but in consequence of appropriations made by law.”

So, for government agencies to receive funding, there must be an appropriations bill.

Twelve subcommittees in Congress review budgets. Then, bills are voted on first in the House and then in the Senate, often not passing. If they fail to pass, they go to a conference committee with members from both chambers, which is then voted on again in the House and the Senate, and then is signed by the president.

If Congress can’t pass a bill, they sometimes pass continuing resolutions to keep funds going to federal agencies. If Congress can’t agree on a continuing resolution, a government shutdown occurs for the specific federal agency.

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Have there always been government shutdowns?

The U.S. government has shut down 21 times, with the three longest durations occurring under Jimmy Carter (17 days), Bill Clinton (21 days) and Donald Trump (35 days).

No government shutdowns occurred in the 1800s, but due to consistent overspending, the Antideficiency Act was enacted in 1884 with amendments made in the 1950s.

U.S. Army Chaplaincy Accounting Chief Scott Turner described, before the Antideficiency Act, spending outside the budget had less serious consequences. He said, now “if we violate the Antideficiency Act, we’re violating federal law.”

Before amendments strengthening the Antidificiency Act were added, overspending continued to be an issue. President Ronald Reagan signed the “Omnibus Budget Reconciliation Act of 1981,” establishing the system that still operates today.

The 1981 act said, “First, if, after the expiration of an agency’s appropriations, Congress has enacted no appropriation for the immediately sub-sequent period, the agency may make no contracts and obligate no further funds except as authorized by law.”

Both of these acts enforced strict adherence to spending within budgets approved by Congress through appropriation bills.

Who is affected?

Only the agencies receiving funding from non-passed appropriation acts are affected.

For example, in 1996, “only three out of the 13 regular appropriations acts had been signed into law” before the first funding gap, according to the Congressional Research Service.

President Clinton then vetoed a continuing resolution “that would have extended budget authority through Dec. 1,” and the subsequent gap “resulted in the furlough of an estimated 800,000 federal workers.”

However, while furloughed federal workers aren’t paid during a shutdown, “Congress routinely provides full back pay to those workers when it ultimately passes appropriations,” according to a Senate staff report.

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The 35-day shutdown in 2019 also impacted the economy and workers, as the National Park Service left many parks open, “but furloughed most rangers and staff,” per The Hill.

National Park Service regional fee manager Cindy David said “the parks lost between $10 million and $11 million in visitor fee revenue during the shutdown.”

Some states will try to keep things running if the federal government shuts down. For example, in Utah, the state government spent $66,000 during the 2019 shutdown to keep national parks open. This month, Utah Senate President Stuart Adams said the state plans to “respond like we did last time” if another government shutdown occurs, according to KSL News.

State House Speaker Brad Wilson, who will step down Nov. 11, acknowledged Utah towns’ heavy economic reliance on national park tourism. He said, “We do need the people back there to do the hard work and make hard decisions. We’ll be ready for what comes.”

Does the U.S. save money during a shutdown?

Shutdowns typically end up costing the country money. In a Senate staff report, the 2013, 2018 and 2019 shutdowns “cost taxpayers nearly $4 billion ... in back pay to furloughed federal workers, and at least $388 million in other costs” such as extra “administrative work, lost revenue, and late fees on interest payments.”

Georgetown law professor Eloise Pasachoff explained that as the public becomes more polarized, the more divided the government becomes, and “the harder a time Congress and the president have trying to get funding approved,” per UMD Public Policy.