The US Treasury Department’s Bureau of the Fiscal Service processes billions of payments worth trillions of dollars each year, acting as the central clearinghouse for almost everything the federal government spends money on,

The U.S. Treasury's payment system won't be touched by Elon Musk's government efficiency team, Treasury Secretary Scott Bessent told Fox Business on Wednesday, adding that any decisions to stop payments would be made by other agencies.

This primer explains what the Bureau of the Fiscal Service does, how it has traditionally been managed by career civil servants, and the risks posed by tampering with the system.