Friday is National Ugly Christmas Sweater Day Since 2011, the recognition of some of Christmas's ugliest fashion has been celebrated on the third Friday of December. Author: TEGNA Updated: 10:55 AM EST December 18, 2020 WASHINGTON — Dec. 18 is National Ugly Christmas Sweater Day, so head to grandma's closet and search for the ugliest sweater out there. Since 2011, the recognition of some of Christmas's ugliest fashion has been celebrated on the third Friday of December. The day is meant to "lighten up the the busy holidays and to show off their absurdly, ugly sweaters," according to the National Day Calendar. Even if you are without an ugly holiday sweater at home, make your own with clashing colors, bells, felt, a collar or even flashing lights.