December is the twelfth and last month of the year in the Julian and Gregorian Calendars. It is one of seven months with the length of 31 days.

December contains the winter solstice in the Northern Hemisphere, the day with the fewest daylight hours, and the summer solstice in the Southern Hemisphere, the day with the most daylight hours (excluding polar regions in both cases). December in the Northern Hemisphere is the seasonal equivalent to June in the Southern Hemisphere and vice versa. In the Northern hemisphere, the beginning of the astronomical winter is traditionally 21 December or the date of the solstice. Meteorological winter begins on 1 December. In the Southern hemisphere, meteorological summer begins on 1 December.

In the Western World the month is strongly associated with Christmas.


December gets 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. The winter days following December were not included as part of any month. Later, the months of January and February were created out of the monthless period and added to the beginning of the calendar, but December retained its name.

Month-long observances

Movable Observances

First Friday

Second Friday after Thanksgiving

First Sunday

Second Monday

Winter Solstice

December 22, unless that date is a Sunday, in which case its moved to the 23rd

Last Friday

December 26, unless that day is a Sunday, in which case the 27th

Fixed observances

December symbols