A type of mortgage (mortgage loan) that is used by private entities (not government agencies) to back and issue non-agency mortgage-backed securities (non-agency MBS). Private entities create and issue these securities to the public investors. Examples of private entities, that issue securities backed by non-agency mortgages, include banks, brokerage firms, and home constructing companies. The non-agency MBS market offers mortgage financing to market players (individual mortgagors) that cannot meet the standards set for holding and investing in agency MBSs.

Non-agency mortgage loans are also known as private-label mortgage.