What is the 250th anniversary of the United States commonly called?

The 250th anniversary of the United States is commonly called the Semiquincentennial.

The word combines “semi,” meaning half, with “quincentennial,” meaning a 500th anniversary. It therefore describes half of five centuries, or 250 years. Other names sometimes appear, including sestercentennial, bisesquicentennial, and quarter millennium, but semiquincentennial is the term most closely associated with the national celebration.

The anniversary falls on July 4, 2026, marking 250 years since the Declaration of Independence was adopted in 1776. The federal United States Semiquincentennial Commission is widely known through the America250 branding.

This anniversary is distinct from the 200th anniversary, or Bicentennial, celebrated in 1976. The next major national milestone will be the Tricentennial in 2076, marking 300 years. The term can be confusing because it describes the anniversary rather than a document, battle, or governmental institution.