List of U.S. state partition proposals

Since the establishment of the United States in 1776, numerous state partition proposals have been put forward that would either set-off a portion of an existing state (or states) in order that this region might either join another state or create a new state. Article IV, Section 3, Clause 1 of the United States Constitution, oftentimes called the New States Clause, grants to the United States Congress the authority to admit new states into the United States beyond the thirteen already in existence at the time the Constitution went into effect (June 21, 1788, after ratification by nine of the thirteen states):

New States may be admitted by the Congress into this Union; but no new State shall be formed or erected within the Jurisdiction of any other State; nor any State be formed by the Junction of two or more States, or Parts of States, without the Consent of the Legislatures of the States concerned as well as of the Congress.

Four Eastern states had Western land claims when the Constitution was written. The New States Clause was designed to give them a veto over whether their western counties could become states. The clause has served this same function since then whenever a proposal to partition an existing state or states has come before Congress. New breakaway states are permitted to join the Union, but only with the proper consents. Of the 37 states admitted to the Union by Congress, Kentucky, Maine, and West Virginia were each set off from an already existing state:

The following is a list of substantive proposals (both successful and unsuccessful) put forward since the nation's founding to partition or set-off a portion of an existing U.S. state (or states) in order that the region might either join another state or create a new state. Proposals to secede from the Union are not included, nor are proposals to create states from either organized incorporated or unorganized U.S. territories. Land cessions made by several individual states to the Federal government during the 18th and 19th centuries are not listed either.

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