The House of Representatives adjourned just before 7:00 pm Friday, with no moves taken to avert a shutdown, and the Senate closed up shop an hour later.
Both are due back in session at noon Saturday.
About three-quarters of the government, including the military and the Department of Health and Human Services, is fully funded until the end of September 2019, leaving 25 percent unfunded as of Saturday.
Most NASA employees will be sent home, as will Commerce Department workers and many at the Departments of Homeland Security, Justice, Agriculture and State.
National parks will remain open, but most park staff will stay home.
While most critical security functions will be operational, the effects of the budget wrangling and uncertainty have cast an air of chaos over the capital, which is also reeling from the resignation announcement Thursday by Defense Secretary Jim Mattis.
Wall Street ended its worst week in a decade with more bruising losses Friday.
And the inability of Washington to accomplish one of its most basic tasks — keeping the government up and running — has caused deep embarrassment and anxiety.
‘Prepared’ for shutdown
“It’s up to the Democrats whether or not we have a shutdown tonight,” Trump said earlier Friday, blaming political opponents for the crisis.
“I hope we don’t,” the president added, but “we’re totally prepared for a very long shutdown.”
Senators told reporters that congressional leaders from both parties were negotiating behind the scenes with White House officials including Vice President Mike Pence, Trump’s son-in-law Jared Kushner, and incoming chief of staff Mick Mulvaney.
The power trio shuttled from one side of the Capitol to the other, seeking a breakthrough with Republicans and Democrats.
It did not come on Friday.
Should they eventually strike a deal, it could swiftly clear Congress and reach the president’s desk, said Senate Republican Bob Corker.
“Now Republicans and Democrats both own the success or failure to fund government.”
One focus of discussion was the $1.6 billion in border security funding that was a part of pending Senate legislation, number two Senate Republican John Cornyn told AFP.