Delaware was the first state to ratify the United States Constitution, doing so on December 7, 1787.
Delaware’s ratifying convention approved the Constitution unanimously, with a vote of 30–0. Its early approval earned the state the nickname “The First State,” a designation that remains part of Delaware’s identity today.
Article VII of the Constitution required approval from conventions in nine states for the document to take effect. New Hampshire became the ninth state to ratify, on June 21, 1788, formally placing the Constitution into operation.
Delaware’s vote was not the same as the Constitution becoming effective nationwide. The remaining original states ratified over the next several years: North Carolina approved it in 1789, while Rhode Island was last, ratifying on May 29, 1790. Pennsylvania, New Jersey, and Georgia followed Delaware in the first month of the ratification process.