Business and professional groups are warning that the current federal funding lapse will cause economic harm to not only government employees and contractors, but the broader U.S. economy and national security as well.

“Federal agencies are not able to use the capabilities of contracting partners to sustain vital operations in a government shutdown,” said James Carroll, CEO of the Professional Services Council. “The national security consequences cause unnecessary risk to U.S. citizens both at home and abroad.”

In a column just days ahead of the Oct. 1 shutdown, Carroll sounded the alarm about multiple risks to the nation.

“Shutdowns negatively impact essential federal missions, harm the U.S. economy, and cause inefficiencies and financial losses that have long-term consequences for our country,” he wrote in his commentary.

The Northern Virginia Chamber of Commerce counts many government contractors among its members. Other NVC member companies such as law firms, accounting firms and real estate firms provide services to government contractors.

The shutdown is an economic threat to federal employees and contractors. Paychecks are delayed and sometimes lost.

“This financial uncertainty immediately hits local businesses, from small storefronts to large firms, affecting everything from revenue streams to long-term investment decisions,” the chamber wrote in their statement.

The chamber’s concerns are backed by stark numbers. PSC estimated that at least 1 million federal contractor employees across the nation will be impacted by the shutdown and most of them will not receive back pay.

“For small and mid-sized businesses, which form the backbone of the federal contracting base, this can mean devastating cash flow disruptions and workforce losses,” Carroll said.

Code for America, a nonprofit organization that works to improve government service delivery, said all Americans will suffer.

“Governing isn’t a game—the well-being of real people hangs in the balance,” said CEO Amanda Renteria. “A government shutdown deals a direct blow to people across the country who are doing everything right but still need assistance to put food on the table, access health care, and make ends meet.”

Renteria said families facing food insecurity, seniors who need health care assistance and veterans will have a harder time accessing needed benefits,