This is the latest accepted revision, reviewed on 5 May 2021. December 31 is the 365th day of the year (366th in leap years) in the Gregorian calendar; It is known by a collection of names including: Saint Sylvester's Day, New Year's Eve or Old Years Day/Night, as the following day is New Year's Day.

December 31 is the 365th day of the year (366th in leap years) in the Gregorian calendar. It is known by a collection of names including: Saint Sylvester's Day, New Year's Eve or Old Years Day/Night, as the following day is New Year's Day. It is the last day of the year; the following day is January 1, the first day of the following year. 1 Events.

December is the twelfth and final month of the year in the Julian and Gregorian Calendars and is the seventh and last of seven months to have a length of 31 days. December got its name from the Latin word decem (meaning ten) because it was originally the tenth month of the year in the Roman calendar, which began in March.

Some of the holidays celebrated in December are Christmas, New Year's Eve, Kwanzaa, and Hanukkah . December is the 12th and last month of every calendar year in the Gregorian calendar, and is one of seven months of the year to have 31 days. December 31 is followed by January 1 of the following year.