Every year, Congress votes on appropriation bills that need to be passed in order to fund most of the federal government’s agencies. If the funding deadline fails to pass by Oct. 1, which is the start of the new fiscal year, the government must partially or fully shut down, depending on which agencies are sufficiently funded.

WHO WILL GET FURLOUGHED?

With the exception of programs funded by other means, the federal government must furlough or stop all non-essential functions until funding is voted on and approved by Congress and signed into law. Here’s a look at agencies that will be furloughed as a result of the government shutdown:

LARGEST U.S. SHUTDOWNS

Lapses of at least five days in funding for federal programs and operations since 1976: