"No taxation without representation" is a political slogan that originated in the American Revolution, and which expressed one of the primary grievances of the American colonists for Great Britain. In short, many colonists believed that as they were not represented in the distant British parliament, any taxes it imposed on the colonists (such as the Stamp Act and the Townshend Acts) were unconstitutional and were a denial of the colonists' rights as Englishmen since Magna Carta.

The firm belief that the government should not tax a populace unless that populace is represented in some manner in the government developed in the English Civil War, following the refusal of parliamentarian John Hampden to pay ship money tax. In the context of British taxation of its American colonies, the slogan "No taxation without representation" appeared for the first time in a headline of a February 1768 London Magazine printing of Lord Camden's "Speech on the Declaratory Bill of the Sovereignty of Great Britain over the Colonies," which was given in parliament. The British government argued for virtual representation, the idea that people were represented by members of Parliament even if they didn't have any recourse to remove then if they were unsatisfied with the representation, i.e. through elections.

The term has since been used by various other groups advocating for representation or protesting against taxes, such as the women's suffrage movement, advocates of District of Columbia voting rights, students seeking to be included in governance in higher education, the Tea Party movement, and others.

According to Michael Hudson, the idea had an early precedent in medieval English law, which established the principle in Magna Carta where chapter 12 states that “[n]o scutage or aid is to be levied in our kingdom, save by the common counsel of our kingdom.”^{[better source needed]}

Since 1660, the English Parliament had exercised control over colonial trade and imposed taxes on imports and exports. By the 1760s, the Americans were being deprived of a historic right. The English Bill of Rights 1689 had forbidden the imposition of taxes without the consent of Parliament. Since the colonists had no representation in Parliament, the taxes violated the guaranteed Rights of Englishmen. Parliament initially contended that the colonists had virtual representation, but the idea "found little support on either side of the Atlantic". The person who first suggested the idea of Parliamentary representation for the colonies appears to have been John Oldmixon, an English annalist of the era of Queen Anne or George I. It was afterwards put forward with approbation by Adam Smith, and advocated for a time, but afterwards rejected and strongly opposed, by Benjamin Franklin."

The 1768 Petition, Memorial, and Remonstrance, which was written by the Virginia House of Burgesses was likewise sent to Parliament, only to be ignored.

The phrase had been used for more than a generation in Ireland. By 1765, the term was in use in Boston, and local politician James Otis was most famously associated with the phrase, "taxation without representation is tyranny." In the course of the Revolutionary era (1750–1783), many arguments were pursued that sought to resolve the dispute surrounding Parliamentary sovereignty, taxation, self-governance and representation.

In the course of the 1760s and 1770s, William Pitt the Elder, Sir William Pulteney, and George Grenville, amongst other prominent Britons and colonial Americans, such as Joseph Galloway, James Otis Jr., Benjamin Franklin, John Adams, the London Quaker Thomas Crowley, Royal Governors such as Thomas Pownall M.P., William Franklin, Sir Francis Bernard, and the Attorney-General of Quebec, Francis Maseres, debated and circulated plans for the creation of colonial seats in London, imperial union with Great Britain, or a federally representative British Parliament with powers of taxation that was to consist of American, West Indian, Irish and British Members of Parliament. Despite the fact that these ideas were considered and discussed seriously on both sides of the Atlantic, it appears that neither the American Congress, nor the colonial Assemblies, nor the British Government in Westminster, at least prior to the Carlisle Peace Commission of 1778, officially proposed such constitutional developments. Governor Thomas Hutchinson apparently referred to a colonial representational proposal when he wrote that,