The United States will mark its next tricentennial in 2076 after America250.
A tricentennial is a 300th anniversary. Since the Declaration of Independence is dated 1776, adding 300 years produces 2076. That year will be the next major national anniversary after the 250th anniversary in 2026.
The terms describe different intervals: the 2026 celebration is a semiquincentennial, meaning 250 years, while 2076 will be a tricentennial, meaning 300 years. The earlier 1976 celebration was the Bicentennial, marking 200 years.
The anniversary sequence is therefore 1976, 2026, and 2076 for 200, 250, and 300 years respectively. These labels refer to elapsed time since the 1776 Declaration rather than to the age of a particular government building or organization.