The Twelve Days of Christmas are the festive days beginning Christmas Day (25 December). This period is also known as Christmastide. The Twelfth Day of Christmas is 5 January^[1], with the celebrations of Christmas traditionally ending on Twelfth Night and is followed by the Feast of the Epiphany on 6 January. In some traditions the first day of Epiphany and the twelfth day of Christmas overlap.

Over the centuries, differing churches and sects of Christianity have changed the actual traditions, time frame and their interpretations. St. Stephen's Day (or Boxing Day), for example, is 26 December in the Western Church and 27 December in the Eastern Church. Boxing Day, the first weekday after Christmas, is observed as a legal holiday in parts of the Commonwealth of Nations and was traditionally marked by the giving of Christmas boxes to service workers (such as postal workers and trades people) in the United Kingdom; 28 December is Childermas or the Feast of the Innocents. Currently, the twelve days and nights are celebrated in widely varying ways around the world. For example, some give gifts only on Christmas Night, some only on Twelfth Night and some each of the twelve nights. are the festive days beginning Christmas Day (25 December). This period is also known as Christmastide. The Twelfth Day of Christmas is 5 January^[1], with the celebrations of Christmas traditionally ending on Twelfth Night and is followed by the Feast of the Epiphany on 6 January. In some traditions the first day of Epiphany and the twelfth day of Christmas overlap.

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