The Thirteen Colonies were the British colonies on the Atlantic coast of North America which broke away from the British Crown in the American Revolutionary War (1775–1783), and joined to form the United States of America.

The Thirteen Colonies in their traditional groupings were: the New England Colonies (New Hampshire, Massachusetts, Rhode Island, and Connecticut); the Middle Colonies (New York, New Jersey, Pennsylvania, and Delaware); and the Southern Colonies (Maryland, Virginia, North Carolina, South Carolina, and Georgia). These colonies were part of British America, which also included territory in The Floridas, the Caribbean, and what is today Canada.

The Thirteen Colonies were separately administered under the Crown, but had similar political, constitutional, and legal systems, and each was dominated by Protestant English-speakers. The first of the colonies, Virginia, was established at Jamestown in 1607. Maryland, Pennsylvania, and the New England Colonies were substantially motivated by their founders' concerns related to the practice of religion. The other colonies were founded for business and economic expansion. The Middle Colonies were established on the former Dutch colony of New Netherland.

Between 1625 and 1775, the colonial population grew from 2 thousand to 2.4 million, largely displacing the region's Native Americans. The population included people subject to a system of slavery, which was legal in all of the colonies. In the 18th century, the British government operated under a policy of mercantilism, in which the central government administered its colonies for Britain's economic benefit.

The 13 colonies had a degree of self-governance and active local elections, and they resisted London's demands for more control over them. The French and Indian War (1754–1763) against France and its Indian allies led to growing tensions between Britain and the 13 colonies. During the 1750s, the colonies began collaborating instead of dealing directly with Britain. With the help of colonial printers and newspapers, these inter-colonial activities and concerns were shared and led to calls for protection of the colonists' "Rights as Englishmen", especially the principle of "no taxation without representation".

Late 18th century conflicts with the British government over taxes and rights led to the American Revolution, in which the Thirteen Colonies joined for the first time to form the Continental Congress and raised the Continental Army, declaring independence in 1776. They fought the Revolutionary War with the aid of the Kingdom of France and, to a much lesser degree, the Dutch Republic and the Kingdom of Spain.

In 1606, King James I of England granted charters to both the Plymouth Company and the London Company for the purpose of establishing permanent settlements in America. The London Company established the Colony of Virginia in 1607, the first permanently settled English colony on the continent. The Plymouth Company founded the Popham Colony on the Kennebec River, but it was short-lived. The Plymouth Council for New England sponsored several colonization projects, culminating with Plymouth Colony in 1620 which was settled by English Puritan separatists, known today as the Pilgrims. The Dutch, Swedish, and French also established successful American colonies at roughly the same time as the English, but they eventually came under the English crown. The Thirteen Colonies were complete with the establishment of the Province of Georgia in 1732, although the term "Thirteen Colonies" became current only in the context of the American Revolution.

In London, beginning in 1660, all colonies were governed through a state department known as the Southern Department, and a committee of the Privy Council called the Board of Trade and Plantations. In 1768, a specific state department was created for America, but it was disbanded in 1782 when the Home Office took responsibility.