Supererogation (Late Latin: supererogatio "payment beyond what is needed or asked", from super "beyond" and erogare "to pay out, expend", itself from ex "out" and rogare "to ask") is the performance of more than is asked for; the action of doing more than duty requires. In ethics, an act is supererogatory if it is good but not morally required to be done. It refers to an act that is more than is necessary, when another course of action—involving less—would still be an acceptable action. It differs from a duty, which is an act wrong not to do, and from acts morally neutral. Supererogation may be considered as performing above and beyond a normative course of duty to further benefits and functionality.

Some philosophers have proposed a corresponding concept of suberogation – whereas supererogatory acts are praiseworthy but not morally required, suberogatory acts are morally discouraged but not prohibited. However, the concept is controversial; with some dispute as to whether suberogatory acts genuinely exist.