The Bureau of the Public Debt borrows the money needed to operate the federal government, provide reimbursable support services to federal agencies, and to account for the resulting debt. Article I, Section 8 of the Constitution empowers the Congress to borrow money on the credit of the United States. Congress has delegated this authority to the Secretary of the Treasury. The Bureau is authorized to conduct such borrowing for the federal government.
The Bureau borrows by selling Treasury bills, notes, and bonds, as well as U.S. Savings Bonds. The Bureau pays interest to investors and when it comes to pay back the loans, the Bureau redeems those securities. Every time when the Bureau borrows or pays back money, it affects the outstanding debt of the United States. The Bureau is responsible for Wholesale Securities Services, Government Agency Investment Services, Retail Securities Services, Summary Debt Accounting, and ARC Franchise Services.