It's National Ugly Sweater Day on December 18th.
More on Ugly Sweater Day and the other days on the 18th below.
We detected 1,093 references to national Ugly Sweater day on 18th the December. There were also a total of 41 other national days mentioned including: Ugly Sweater, Ugly Christmas Sweater, Christmas Jumper and Free Shipping Day.
The day shown for 'National Ugly Sweater Day' is shown as we detected that day mentioned the most out of all the references to national days there were on December the 18th across social media. Our algorithms examine all of the references to National Days across social media and updates whatnationaldayisit.com hourly, with our homepage displaying the current national day. This crowdsourcing of data method to assess the National Day date is used as opposed to being connected with any Government sacntioned lists :D Hurrah for democracy by concensus!