Thirteen British colonies adopted the United States Declaration of Independence in 1776.
The colonies were New Hampshire, Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Pennsylvania, Delaware, Maryland, Virginia, North Carolina, South Carolina, and Georgia. Together, they declared that they were free and independent states rather than colonies of Great Britain.
The number is sometimes confused with the votes on the Declaration’s adoption. On July 4, 1776, twelve colonial delegations voted in favor while New York abstained because its delegates had not yet received authorization. New York later joined the decision after its provincial convention approved independence.
The phrase “thirteen colonies” describes the British colonies that became the original United States. It does not mean that every later U.S. state existed in 1776. The new nation expanded westward and admitted additional states during the following centuries.