The Stamp Act Congress (October 7 – 25, 1765), also known as the Continental Congress of 1765, was a meeting held in New York City in the colonial Province of New York. It included representatives from most of the British colonies in North America, which sought a unified strategy against newly imposed taxes by the British Parliament, particularly the Stamp Act 1765. It was the second such gathering of elected colonial representatives after the Albany Convention of 1754 at the outbreak of the French and Indian War. Massive debts from that war, which ended in 1763, prompted the British Parliament to implement measures to raise revenues from the colonies. The Stamp Act 1765 required the use of specialty stamped British paper for all legal documents, newspapers, almanacks, and calendars, and even playing cards and dice. When in force, it would have an impact on practically all business in the colonies, starting on November 1, 1765. Resistance to it came especially from lawyers and businessmen, but was broadly protested by ordinary colonial residents.

Delegates from nine colonies attended the Congress. All of the attending delegations were from the Thirteen Colonies that eventually launched the American Revolution, breaking from British colonial rule to form the United States. Although sentiment was strong in some of the other colonies to participate in the Congress, a number of royal governors took steps to prevent the colonial legislatures from meeting to select delegates.

The Congress met in the building where Federal Hall now stands and was held at a time of widespread protests in the colonies, some violent, against the Stamp Act's implementation. The delegates discussed and united against the act, issuing a Declaration of Rights and Grievances in which they claimed that Parliament did not have the right to impose the tax because it did not include any representation from the colonies. Members of six of the nine delegations signed petitions addressed to Parliament and King George III objecting to the act's provisions.

The extralegal nature of the congress caused alarm in Britain, but any discussion of the congress's propriety were overtaken by economic protests from British merchants, whose business with the colonies suffered as a consequence of the protests and their associated non-importation of British products. The economic issues prompted the British Parliament to repeal the Stamp Act 1765, but it passed the Declaratory Act the same day, to express its opinion on the basic constitutional issues raised by the colonists; it stated that Parliament could make laws binding the American colonies "in all cases whatsoever."

In the aftermath of the French and Indian War, the British Parliament sought to increase revenues from its overseas colonies, where the cost of stationing troops had become significant. Parliament first passed the Sugar and Currency Acts in 1764, specifically aimed at raising money for the Crown by tighter regulation of colonial trade. The acts had brought protests from colonial legislatures but had skirted the idea of direct taxation by structuring their revenues as trade-related excise duties. British Prime Minister George Grenville noted at the time of the Sugar Act's passage that a stamp tax might also be necessary, immediately raising concern and protest in the colonies.

With the Stamp Act 1765, Parliament attempted to raise money by direct taxation on the colonies for the first time. The act required that all sorts of printed material carry a stamp (purchased from a government agent) to show that the tax had been paid. The use of the stamped paper was required for newspapers, books, court documents, commercial papers, land deeds, almanacs, dice, and playing cards. The revenue was to help finance the operations of the empire, including the cost of stationing troops in the colonies, without seeking revenue through the established colonial assemblies, which had a history of failure.

In June 1765, the Massachusetts Assembly drafted a letter, which was sent to the legislatures of "the several Colonies on this Continent" to "consult together on the present circumstances of the colonies." Nine of the British America continental colonies ultimately selected delegates to attend the congress: Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Pennsylvania, Delaware, Maryland, and South Carolina. All of the delegates selected were members of their colonial legislative bodies.

The methods by which delegates were selected were in some cases unorthodox. In Delaware, then known as the "Three Lower Counties" of the Penn proprietors, assembly members held informal meetings in each of the three counties, in each case selecting the same three delegates. In New York, the assembly had been prorogued and was judged unlikely to be summoned by Lieutenant Governor Colden to consider the Massachusetts letter. The assembly's committee of correspondence, consisting of its New York City delegates, discussed the letter and decided under the circumstances to assume the authority to represent the colony. New Jersey's assembly politely declined to send delegates before adjourning in late June, but after political sentiment against the Stamp Act became more pronounced, Speaker Robert Ogden called an extralegal assembly (since only the governor could officially call it into session) in late September that chose three delegates. Governor William Franklin was upset at the action but took no action beyond protesting the unusual meeting. Maryland's assembly, prorogued because of a smallpox outbreak, was finally called into session by Governor Horatio Sharpe to consider the Massachusetts letter on September 23, and delegates were chosen.