Delegates signed the United States Constitution on September 17, 1787, a date remembered in America250 history.
The signing took place at Independence Hall in Philadelphia at the end of the Constitutional Convention. Thirty-nine delegates endorsed the document, representing twelve states; Rhode Island had declined to send delegates. The Constitution then required ratification by the states before it could become the nation’s governing framework.
The signing date is not the same as the Constitution’s effective date. New Hampshire became the ninth state to ratify it on June 21, 1788, satisfying the document’s ratification requirement. The new federal government began operating in 1789, and George Washington took the presidential oath on April 30 of that year.
Another common mix-up is confusing September 17, 1787, with July 4, 1776, the date associated with the Declaration of Independence. The two documents belong to different stages of the nation’s founding.