What is the official name for the United States’ 250th-anniversary celebration?

The official name for the United States’ 250th-anniversary celebration is the United States Semiquincentennial.

A semiquincentennial is an anniversary of 250 years. The word combines “semi,” meaning half, with “quincentennial,” referring to 500 years. In ordinary public use, America250 is the shorter branding associated with the nationwide commemoration.

The anniversary specifically commemorates the 250th anniversary of the Second Continental Congress adopting the Declaration of Independence on July 4, 1776. It is therefore also tied to the 250th Independence Day in 2026.

Other terms have appeared in historical and cultural usage, including sestercentennial, quarter-millennium, and bisesquicentennial. However, the principal Wikipedia title and standard formal name for the national anniversary is United States Semiquincentennial. The name distinguishes the event from the bicentennial of 1976 and the future tricentennial of 2076.