List of U.S. National Historic Landmarks by state

The program was formally inaugurated with a series of listings on October 9, 1960; as of August 21, 2020, there are 2,597 designated landmarks.

The program is administered by the National Park Service (NPS), a branch of the Department of the Interior.

The National Park Service determines which properties meet NHL criteria and makes nomination recommendations after an owner notification process.

This designation provides indirect, partial protection of the historic integrity of the properties via tax incentives, grants, monitoring of threats, and other means.

Five listings are found in Pacific island nations with which the U.S. has established a free association agreement, and one listing, the American Legation in Tangier (the nation's first foreign public property), is found in the unaffiliated Kingdom of Morocco.