Nation Flag Day is June 14: Here’s what you need to know about flag etiquette June 14, 2019 Amy J. Vellucci, Knoxville (Tenn.) News Sentinel Comments Off on Flag Day is June 14: Here’s what you need to know about flag etiquette Since 1942, the United States has followed the U.S. Flag Code, a long list of rules and guidelines for displaying and respecting the American flag.