The country won't have money to fund some services, which means, come next week, life could be a lot more difficult.
"You've got an unprecedented demand here," says political science professor Mike Miller when discussing the stalled federal budget.
Republicans, which have a majority in the U.S. House, say they won't sign any of it unless funding for the Affordable Care Act is scrapped. It's leaving trillions of dollars hanging in the balance.
"I think we're way past scare tactics. The President has made it clear that the ACA is not part of a compromise. If the House of Representatives doesn't back down from that, there will be a shut-down."
What would that be like?
"People would notice right away."
Certain federal services would just stop.
"National parks would shut down, and if you're taking a trip, your passports are going to be delayed."
Those fall under what's called the "non-excepted" category; jobs that aren't absolutely vital. People like air-traffic controllers, federal prison guards and the military would all keep working, they just won't get paid for it.
But, if weeks go by, there could be delays in social security and unemployment checks.
"Every time these things happen, there's different context."
Miller says it's difficult to predict what could happen, but says, one thing a lot of people will lose is confidence.
"People, at the end of the day, expect their government to be functioning and when we see something like this, it suggests to people that the folks that they've elected and are paying to do a job, have not been doing it."
Congress has until Monday to pass a budget. The last time there was a shutdown was in 1995. It lasted four weeks.