Thirty-nine delegates signed the United States Constitution on September 17, 1787.
The signing took place at Independence Hall in Philadelphia at the final session of the Constitutional Convention. Although 74 delegates had been chosen, 55 attended at some point and 39 ultimately signed. The delegates represented twelve states because Rhode Island declined to send representatives to the convention.
The signing figures are often confused because the convention’s attendance changed over time. Some delegates left before the final session, and three men who remained—Edmund Randolph, George Mason, and Elbridge Gerry—refused to sign the completed document. John Dickinson was absent because of illness, and George Read signed for him by proxy.
George Washington, who presided over the convention, signed first. The Constitution then went to the states for ratification. It established the federal framework that replaced the Articles of Confederation in 1789, creating the governing structure of the United States that remains in force today.