A royal family is the extended family of a king or queen regnant and typically includes the spouse of the reigning monarch, surviving spouses of a deceased monarch, the children, grandchildren, brothers, sisters, and cousins of the reigning monarch, as well as their spouses.

In some cases, royal family membership may extend to great grandchildren and more distant descendants of a monarch. In certain monarchies where voluntary abdication is the norm, such as the Netherlands, a royal family may also include one or more former monarchs. The specific composition of royal families varies from country to country