The U.S. government can shut down indefinitely as long as Congress does not pass a funding bill to authorize government spending. There is no fixed maximum duration for a government shutdown; it lasts until lawmakers reach an agreement and appropriate funds to reopen government operations. The longest government shutdown in U.S. history lasted 35 days, from December 22, 2018, to January 25, 2019, during which 380,000 federal workers were furloughed and another 420,000 worked without pay.
Shutdowns occur when Congress fails to pass annual appropriations bills or continuing resolutions by the start of the fiscal year on October 1. Without authorized funding, federal agencies must suspend operations except for essential functions. The shutdown continues until a funding agreement is reached. Most shutdowns in recent decades have lasted a few days to several weeks, but in theory, it could last longer if budget disagreements persist.
In summary, a government shutdown has no predefined time limit and can endure as long as there is no consensual funding agreement between Congress and the President. The current record for the longest shutdown is 35 days.
