A leap year (also known as an intercalary year or a bissextile year) is a year containing one additional day (or, in the case of lunisolar calendars, a month) added to keep the calendar year synchronized with the astronomical or seasonal year. Because seasons and astronomical events do not repeat in a whole number of days, calendars that have the same number of days in each year drift over time with respect to the event that the year is supposed to track. By inserting (also called intercalating) an additional day or month into the year, the drift can be corrected. A year that is not a leap year is called a common year.

A leap year is a year with an extra day. Leap year may also refer to:

• Leap Year (1924 film) – American film
• Leap Year (1932 film) – British film
• Leap Year (2010 film) – American film
• Leap Years – a 2001 drama television series
• The Leap Years – 2008 Singaporean film, aka Leap of Love
• Año bisiesto (Leap Year) - a Mexican film directed by Michael Rowe that won the 2010 Caméra d'Or at the Cannes Film Festival