What is the 250th anniversary of American independence called?

The 250th anniversary of American independence is called the Semiquincentennial.

The word combines Latin-derived parts associated with half and five hundred, producing a term for half of 500 years, or 250 years. It is less familiar than bicentennial, which describes a 200th anniversary, but it is the formal name used for the 2026 national observance.

The celebration is also known by several alternative terms, including sestercentennial, bisesquicentennial, and quarter millennium. America250 is the shorter branding used by the United States Semiquincentennial Commission and its partners.

The event commemorates the 1776 Declaration of Independence. It does not mark the 250th anniversary of the Constitution, which dates from 1787, or the 250th anniversary of the first presidential inauguration, which occurred in 1789.