By Kate Davidson 

What happens at 12:01 a.m.?

In short, not much. Most federal agencies are closed on the weekend, so the effect of any shutdown may initially be muted. The White House has said national parks will remain open, though trash won't be picked up, and the Transportation Security Administration will continue to screen bags and passengers at airports across the country. The Smithsonian museums in Washington are expected to have enough funding to operate on Saturday and Sunday, but will close next week if the government doesn't reopen.

What do federal workers do?

Federal employees report to work for four hours of the first working day of a shutdown -- in this case, Monday morning -- to learn whether they are subject to furloughs or considered exempt, put up "out of office" notices, secure property, turn in their mobile devices and tie up loose ends for an indefinite period.

How many federal workers are affected?

During the 2013 shutdown, the Office of Management and Budget estimated that approximately 850,000 workers were furloughed per day initially, or 40% of the federal workforce, though that number fluctuated.

Will they get paid?

Not immediately. Federal workers may get awarded back pay, which is what happened in 2013, but not everyone on Capitol Hill is convinced that would happen this time. In some states, workers can file for unemployment compensation, but they would have to pay it back if they are awarded back pay.

Employees will still receive paychecks for hours worked before the shutdown, according to guidance from the OMB.

Can federal workers who want to work show up anyway?

No. The law prohibits the government from accepting any voluntary work from federal employees -- even those who don't want to fall behind on that big project.

Are any federal agencies open?

Some agencies can continue to operate for a limited time during a shutdown, and the administration has fairly wide latitude to determine which employees are deemed essential. The judicial branch could continue to operate for a limited time using funds from court filings and other fees. Independent agencies that don't receive their funding from Congress -- such as financial regulators who are funded by fees on financial firms -- would stay open. In many cases however, government operations would be significantly scaled back. For example, the 16-day shutdown in 2013 delayed almost $4 billion in tax refunds from being issued and forced temporary cutbacks in the Centers for Disease Control and Prevention's flu-season monitoring program.

Will I get mail?

Yes, the U.S. Postal Service continues to operate during a shutdown.

Will government payments to private citizens continue, such as Social Security checks?

Yes, Social Security and Medicare payments, as well as federal retiree benefits, will still be made. They aren't funded by annual appropriations -- which is what the spending bill would authorize -- and the workers who send them out have been deemed necessary.

How long will it last?

The shutdown would end as soon as the president signs a bill authorizing new spending, either for a temporary period -- the most likely scenario -- or until the end of the fiscal year on Sept. 30. The last shutdown, in October 2013, lasted for 16 days. The previous shutdown before that lasted for 21 full days, ending on Jan. 6, 1996.

Write to Kate Davidson at kate.davidson@wsj.com

(END) Dow Jones Newswires

January 19, 2018 17:42 ET (22:42 GMT)

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