Fixed income is a type of income that is not subject to change and is usually received on a regular basis. A fixed income can come from a variety of sources, such as investments, pensions, annuities, and Social Security. One example of a fixed income is a STIPEND, which is a fixed sum of money paid regularly for services or to support a person or cause. Stipends are typically paid to students, interns, or volunteers in exchange for their work.