No Kings Day is not a traditional or official holiday but rather a term used by organizers for protests against what they describe as authoritarian policies of President Donald Trump. The initial No Kings protests took place on June 14, 2025, coinciding with the U.S. Army's 250th Anniversary Parade and Trump's 79th birthday. A second wave of No Kings protests is scheduled for October 18, 2025, with over 2,500 events planned across the United States and internationally. Thus, "No Kings Day" refers specifically to these protest days rather than being an annual or fixed holiday. The key dates involved so far are June 14, 2025, and October 18, 2025, with the latter being the upcoming one as of today. These are planned days of demonstrations rather than recognized holidays or celebrations named "No Kings Day".

In summary, No Kings Day is observed on June 14 and October 18, 2025, as designated protest days against Trump's administration and is not a recurrent holiday beyond these protest events.