Delaware was the first state to ratify the U.S. Constitution under Article Seven, approving it on December 7, 1787.
Article Seven required ratification by conventions in at least nine of the 13 states for the Constitution to take effect. Delaware’s convention approved the document unanimously, with a vote of 30–0. Pennsylvania ratified five days later, followed by New Jersey and Georgia.
Delaware’s first-place status is sometimes confused with New Hampshire’s role. New Hampshire was the ninth state to ratify, on June 21, 1788, which supplied the ninth approval needed to put the Constitution into effect. Rhode Island was the last of the original 13 states, ratifying on May 29, 1790.
The 250th anniversary of the United States in 2026 provides an opportunity to revisit this early constitutional milestone. Delaware’s unanimous vote helped begin the sequence of state approvals that replaced the Articles of Confederation with the present federal system.