What if the US government shuts down?

The US is moving closer to another government shutdown after the lower house of Congress failed to pass a spending bill that would keep federal agencies open.

The funding is set to expire at midnight on Friday unless Republicans and Democrats can agree on a way forward.

Here's a breakdown of how we got here and what it means for Americans — and for Donald Trump.

Many federal government agencies rely on annual funding approved by Congress.

Each year, these agencies submit their requests, which Congress must pass and the president must sign into law the budget legislation for the next fiscal year.

If no agreement is reached, then all non-essential, discretionary functions of the US government cease.

In September, the two sides agreed on a bill to preserve state funding until December 20.

This week, three days before lawmakers go on holiday recess, House Speaker Mike Johnson, a Republican, introduced a bill to extend the funding through March.

It was negotiated with Democratic leadership, but it included some measures such as a raise for lawmakers, which made some Republicans unhappy.

Tech billionaire Elon Musk, a Trump ally, publicized his opposition to it, and then the president-elect signaled that he wanted his party to kill him, which it did.

A second, watered-down bill reached the floor Thursday night, but failed to muster enough votes to pass.

If no deal is reached by midnight, the US will have its first shutdown since early 2019.

Essential workers continue to work as usual, some without pay, while civil servants deemed non-essential have been temporarily placed on unpaid leave.

Border protection, inpatient medical care, law enforcement and air traffic control will continue to work.

But services such as the food assistance program, federally funded preschool, student loan issuance and food inspections and national parks will be limited or closed.

While Social Security and Medicare checks are being mailed, benefit verification and card issuance stops.

There may also be travel delays if the outage drags on.

“Prolonged shutdowns could mean longer wait times at airports,” Transportation Security Administration spokesman Carter Langston said.

The Tesla boss is tasked with identifying cost cuts by co-leading the proposed Department of Government Efficiency (DOGE).

It's not an official government department, but it has promised to find $2 trillion in savings.

On Wednesday, he made dozens of posts on X, the platform he owns, to express his distaste for Mike Johnson's bill.

Expanding on some false claims about what was in the bill, he called it criminal and outrageous.

After Musk sparked opposition, Trump and J.D. Vance, the incoming vice president, delivered the final blow to Johnson's deal that evening.

They said in a joint statement that they wanted streamlined legislation without the Democratic-backed provisions that Johnson had included.

They also called on Congress to raise or eliminate the debt ceiling, which determines how much the government can borrow to pay its bills.

Johnson promised to find a solution on Friday, so there will be plenty of arguments on Capitol Hill as the clock ticks down.

But to get the necessary support in the House to pass, he will need Democratic votes.

Democrats say they will only support the original bill, which Trump and Musk opposed.

If no deal is reached, US federal agencies will shut down at midnight.

Quite common. President Ronald Reagan presided over eight shutdowns during his tenure — though all were relatively brief.

And there were three when Donald Trump was president, including the longest on record at 36 days, which ended in January 2019.

This happened because of disagreements over funding for a wall on the border with Mexico.

Congressional Budget Office (CBO) estimated to reduce economic output with about $11 billion, including $3 billion it never recovered.

The shutdown over budgets is almost unique to US politics.

Under the US system, the various branches of government must reach agreement on spending plans before they become law.

In most countries, the budget vote becomes a vote of confidence in the government itself. But since the US has equal and often separate branches of government, this is not the case.

Also known as the debt limit, this is a law that limits the total amount of money the government can borrow to pay its bills.

This includes paying federal employees, the military, Social Security and Medicare, as well as interest on the national debt and tax refunds.

From time to time, the US Congress votes to raise or suspend the ceiling so that it can borrow more.

Trump's addition of that condition to the deal was an unexpected request that made it difficult for right-wing Republicans, who often oppose increased government spending, to support the bill.

The debt ceiling will have to be raised in the coming months regardless of the promised efficiency stimulus.

But by demanding it happen now, some analysts believe Trump is signaling the cost of his proposed tax cuts and tighter border restrictions will test the ceiling. And he prefers the raise battle to happen before he takes office.

Democrats are usually in favor of raising the debt ceiling without limits, but now they are in no mood to help Republicans.

The risk for Trump is that the mini-rebellion will tear away the mantle of invincibility he has been wearing since the election.

And it raises questions about how smoothly his party will be able to deliver on campaign promises that require legislation.