Treasury bills

United States Treasury securities are government debt instruments issued by the United States Department of the Treasury to finance the national debt of the United States. Treasury securities are often referred to simply as Treasuries. Since 2012 the management of government debt has been arranged by the Bureau of the Fiscal Service, succeeding the Bureau of the Public Debt.

There are four types of marketable treasury securities: Treasury bills, Treasury notes, Treasury bonds, and Treasury Inflation Protected Securities (TIPS). There are also several types of non-marketable treasury securities including State and Local Government Series (SLGS), Government Account Series debt issued to government-managed trust funds, and savings bonds. All of the marketable Treasury securities are very liquid and are heavily traded on the secondary market. The non-marketable securities (such as savings bonds) are issued to subscribers and cannot be transferred through market sales.

Federal Reserve Banks are required to hold collateral equal in value to the Federal Reserve notes that the Federal Reserve Bank puts into circulation. This collateral is chiefly held in the form of U.S. Treasury debt and government-sponsored enterprise securities.

To finance the costs of World War I the U.S. Government increased income taxes (see the War Revenue Act of 1917) and government debt, called war bonds. Traditionally, the government borrowed from other countries, but there were no other countries from which to borrow in 1917.

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