Wigilia (Polish pronunciation: [viˈɡilja]) is the traditional Christmas Eve vigil supper in Poland, held on December 24. The term is also often extended to the whole day of the Christmas Eve, extending further into the midnight Mass held at Roman Catholic churches all over Poland and large Polish communities worldwide at midnight preceding the Christmas Day. In this usage, the supper itself is rather called "wieczerza" or "wieczerza wigilijna", using an Old Polish word meaning "dinner", "large supper", stemming from Proto-Indo-European root *vesper - evening. The Last Supper translates into Polish as "ostatnia wieczerza".

The word "Wigilia" derives from the Latin verb vigilare, "to watch", and literally means 'eve'. The feasting traditionally begins once the First Star has been sighted (usually by children) in the heavens at dusk (around 5 p.m.). Therefore Christmas is also sometimes called "Gwiazdka" (the little star, referring to the Star of Bethlehem).

Children usually decorate the Christmas tree on this day (if it has not been set up before). A bundle of hay is placed under the tablecloth or in each of the four corners of the room to symbolize the fact that Jesus was born in a manger.