National Big Butt Day is an informal, internet-created “holiday” most commonly listed as falling on October 19 each year.

What this “day” actually is

  • It is not an official national holiday recognized by any government or major calendar authority.
  • It shows up mainly on “fun/novelty holiday” sites and social media as a playful celebration of curvy bodies and body positivity focused on the butt.
  • The origin is unclear; it appears to have grown out of meme culture, celebrity influence, and online “national day” lists over the last decade.

Related “butt” days online

There are a bunch of similar tongue‑in‑cheek days floating around:

  • “National Ass Day” is often listed as October 17 on novelty and holiday-tracking sites.
  • Some sites distinguish between “Big Butt Day,” “Ass Day,” “Bum Day,” or “Booty Day,” but these are all informal and not standardized across calendars.

How people treat National Big Butt Day

  • Novelty holiday sites frame it as a day to appreciate larger buttocks, often connecting it to body positivity and pop culture references like Sir Mix-a-Lot or celebrities known for curvier figures.
  • Social media posts around October 19 sometimes use hashtags like #NationalBigButtDay or similar tags to share jokes, selfies, or fitness content.

Quick answer recap

  • Date most commonly cited: October 19 (unofficial).
  • Status: Internet/novelty day, not a real national holiday.

Information gathered from public forums or data available on the internet and portrayed here.