An agency bond, also known as an agency security or simply 'agencies', is a bond issued by institutions in the United States that were originally established by the American government to promote certain social goals, such as encouraging home ownership or providing student finance.

Well-known examples of such institutions are the Federal National Mortgage Association (FNMA or Fannie Mae), the Government National Mortgage Association (GNMA or Ginnie Mae), the Federal Home Loan Mortgage Corporation (FHLMC or Freddie Mac), and the Federal Home Loan Banks.

Although these government agencies operate independently, they are seen by the market as institutions for which the American government implicitly offers some guarantee. As a result, agency bonds have a lower credit rating than American government bonds, such as Treasury bonds.