Founder's Day
Founder's Day, Founders Day, or Founders' Day and variations may refer to:
- Founder's Day, a holiday of the American Revolution
- Founders Day, an observance and former public holiday in South Africa
- Founders' Day, a former public holiday in Rhodesia
- "Founder's Day" (The Vampire Diaries), an episode of the TV series The Vampire Diaries
- Founders' Day, a Scouting commemoration associated with Scouts' Day
- Founder's Day, a public holiday in Ghana