Colorado will mark its 150th statehood anniversary alongside America250 in 2026.
Colorado entered the Union on August 1, 1876, earning the nickname “the Centennial State” because its admission came during the nation’s centennial year. In 2026, Colorado’s sesquicentennial, or 150th anniversary, coincides with the United States’ semiquincentennial, or 250th anniversary.
The state created the America 250–Colorado 150 Commission to plan the twin commemoration. The commission operates through History Colorado and supports historical activities, public ceremonies, educational programs, document publication, and other events. This gives Colorado a distinctive double anniversary: one marking national independence and another marking statehood.
The timing can be confusing because Colorado’s statehood anniversary is not the same as the anniversary of its territorial organization. Colorado Territory was established in 1861, while statehood came fifteen years later in 1876. The 2026 state celebration specifically commemorates admission to the Union, not the creation of the territory.