The U.S. Department of Health, for example, has in place a contingency plan for agency operations during a government shutdown, with 49,625 staff members considered essential and 40,887 staff members being furloughed, which breaks down to 55% retained and 45% furloughed.

During a shutdown, the federal government would be unable to pay its millions of employees, including members of the military and reservists, just before the holidays.

The House passed a spending bill that will avoid a government shutdown. Republicans withdrew from a prior deal after criticism from Donald Trump and Elon Musk.