List of National Historic Landmarks in Missouri

[1] Two sites in Missouri were once a National Historic Landmark but later had their designations withdrawn when they failed to meet the program's criteria for inclusion.

The NPS is responsible for determining which sites meet the criteria for designation or withdrawal as an NHL as well as identifying potential candidates for the program, through theme studies.

The NPS and the National Park System Advisory Board then meet to determine the historical significance of these candidates.

The final decision regarding a site's designation as a National Historic Landmark is made by the U.S. Secretary of the Interior.

This usually occurs when the property undergoes any change that reduces or eliminates its national significance, usually demolition, addition, or other alterations.