United States Postal Service (USPS) workers load mail into delivery trucks outside a post office in Royal Oak, Michigan, U.S. August 22, 2020.

The U.S. Postal Service will not be affected by a looming government shutdown that could begin on Oct. 1.

Congressional leaders from both parties have failed to strike a deal to pass funding legislation to avert the shutdown, which would render a stoppage to some government services.

If they don't come to an agreement, parts of the government will close on Oct. 1, the first day of the U.S. government's 2026 fiscal year.

The shutdown appeared likely after President Donald Trump and top congressional leaders emerged from a private White House meeting on Monday, Sept. 29 without a deal. Republicans are pushing a makeshift solution that would extend current funding until Nov. 21, while Democrats are continuing to fight for changes related to health care.

In a government shutdown, services deemed essential will continue, while other non-essential functions will close or cut staffing.

Are mail service, post offices affected in a government shutdown?

Postal services, including mail delivery, will continue even if the government shuts down.

In a Sept. 25 statement, the U.S. Postal Service confirmed that its operations will not be interrupted in a shutdown, and post offices will remain open for "business as usual."

"Because we are an independent entity that is generally funded through the sale of our products and services, and not by tax dollars, our services will not be impacted by a government shutdown," the statement said.

What is a government shutdown?

Each fiscal year, Congress allocates funding for federal agencies to operate.

However, if lawmakers do not agree on appropriations or a temporary spending bill, some federal agencies must effectively shut down or stop normal spending, according to the Office of Personnel Management.

Some jobs or services are deemed essential and continue to operate in the event of a shutdown.

What essential services will not be affected in a government shutdown?

In addition to postal service, some federally-run agencies will continue to operate in the event of a government shutdown.

Social Security services, Medicare and air traffic control are deemed essential services, while "nonessential" work such as national park operations will stop.

How long could a government shutdown last?

Since 1977, there have been 21 federal government shutdowns. In total, they lasted 121 days, or an average of almost eight days per shutdown.

The longest government shutdown in the last five decades, which lasted 35 days, occurred under the first Trump administration from December 2018 to January 2019.

Two other shutdowns took place in Trump's first term: the first lasted three days in January 2018, and the second lasted a few hours in February 2018.

Melina Khan is a national trending reporter for USA TODAY. She can be reached at melina.khan@usatoday.com.

Contributing: Bart Jansen, Zac Anderson, Saman Shafiq, USA TODAY

This article originally appeared on USA TODAY: Are mail service, post offices affected by a government shutdown? What to know

Reporting by Melina Khan, USA TODAY / USA TODAY

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