Delaware was the first U.S. state to ratify the Constitution, doing so on December 7, 1787.
Delaware’s ratifying convention approved the Constitution unanimously, with all 30 delegates voting in favor. Its early approval earned the state the nickname “The First State,” which remains Delaware’s official state nickname.
The Constitution required ratification by conventions in nine of the thirteen states before it could take effect. New Hampshire became the ninth state to ratify, on June 21, 1788. Delaware’s action came nearly six months earlier, before the document had secured enough approvals to become operative.
Delaware is sometimes confused with Pennsylvania or New Jersey because both were among the first states to ratify. Pennsylvania ratified five days later, on December 12, 1787, while New Jersey followed on December 18.