What is the 250th anniversary of U.S. independence, celebrated by America250 in 2026, called?

The 250th anniversary of U.S. independence, celebrated by America250 in 2026, is called the Semiquincentennial.

The word combines “semi,” meaning half, with “quincentennial,” relating to 500 years. It describes half of a 500th anniversary, or 250 years. The term is less familiar than “bicentennial,” which describes 200 years, but it is the formal name used for the 2026 national commemoration.

The event marks the anniversary of the Declaration of Independence, adopted by the Second Continental Congress on July 4, 1776. America250 is the commonly used name associated with the congressional United States Semiquincentennial Commission and its commemorative programs.

Other terms have appeared in discussions of the anniversary, including “sestercentennial,” “bisesquicentennial,” and “quarter millennium.” However, “Semiquincentennial” is the standard name used for the national observance.