How the Constitution Is Amended: The Article V Process Explained
The U.S. Constitution has been amended only 27 times in more than two centuries. That rarity is intentional. Article V creates a demanding process that requires supermajority agreement across multiple levels of government — and understanding it explains why constitutional change is so difficult to achieve.
Published June 28, 2026The Constitution is the supreme law of the United States. Ordinary legislation can be passed or repealed by simple majorities; the Constitution requires far more. Article V of the Constitution specifies the only legitimate pathways for formal amendment, and both involve clearing multiple hurdles that simple majorities cannot clear on their own.
Two paths to proposing an amendment
The first and historically dominant path for proposing an amendment runs through Congress. A proposed amendment must pass both the House of Representatives and the Senate by a two-thirds vote in each chamber. This threshold is substantially higher than the simple majority needed to pass ordinary legislation, and it means that a significant minority can block a proposal that a majority supports.
The second path is a constitutional convention called by Congress at the request of two-thirds of state legislatures — currently 34 states. This method has never been used. It was included by the founders as a safeguard allowing states to propose amendments if Congress refused to act, but it has remained theoretical partly because of uncertainty about what rules would govern such a convention and what scope it could legitimately address.
Ratification: the harder step
Proposing an amendment is only the beginning. Before it becomes part of the Constitution, an amendment must be ratified. Congress can specify which of two ratification methods applies when it proposes an amendment.
The standard method requires ratification by the legislatures of three-fourths of the states — currently 38 states. Congress can alternatively require ratification by state conventions rather than legislatures; this method was used only once, for the Twenty-First Amendment, which repealed Prohibition in 1933.
The three-fourths threshold means that 13 states can block ratification of any amendment. Given the diversity of American states, this is a meaningful barrier. An amendment that enjoys broad national support but faces concentrated opposition in a region of the country may fail even if the majority of Americans favor it.
Time limits and the ratification period
Congress has sometimes included time limits in proposed amendments, typically requiring ratification within seven years. The Twenty-Seventh Amendment, which addresses congressional pay raises, illustrates how the process can play out over unexpected timelines: it was proposed by Congress in 1789 as part of the original Bill of Rights package, but was not ratified by a sufficient number of states until 1992 — more than 200 years later. Because no deadline was attached, the ratification was held to be valid despite the extraordinary lapse of time.
A brief history of the amendments
The first ten amendments — the Bill of Rights — were ratified together in 1791, just two years after the Constitution took effect. They were the product of ratification debates in which several states agreed to support the Constitution only on the condition that specific protections for individual rights would follow promptly. The Bill of Rights protects freedoms of speech, press, and religion; the right to keep and bear arms; protections against unreasonable searches and criminal self-incrimination; and the right to a jury trial, among others.
The next three amendments, ratified after the Civil War, transformed the constitutional order. The Thirteenth Amendment (1865) abolished slavery. The Fourteenth Amendment (1868) granted citizenship to all persons born or naturalized in the United States and prohibited states from denying due process or equal protection of the laws — provisions that have become the basis for most modern civil rights litigation. The Fifteenth Amendment (1870) prohibited denying the right to vote based on race.
Later amendments addressed other expansions of the democratic franchise. The Nineteenth Amendment (1920) extended voting rights to women. The Twenty-Fourth Amendment (1964) abolished poll taxes in federal elections. The Twenty-Sixth Amendment (1971) lowered the voting age to 18.
Why the process is designed to be difficult
The high thresholds for proposal and ratification reflect a deliberate judgment: constitutional rules should not shift easily with momentary political majorities. Ordinary laws can respond to changing circumstances; constitutional provisions are meant to be more durable. Requiring supermajority agreement at multiple levels forces a degree of consensus that filters out changes that are popular in the short term but may not reflect settled, broad agreement.
Critics argue that the high bar for amendment has left the Constitution unable to adapt to changed circumstances and has given the courts too much power to interpret older provisions in ways their authors could not have anticipated. Defenders argue that the demanding process prevents constitutional instability and the kind of frequent rewriting that has characterized constitutions in other countries.
Whatever one's view of that debate, understanding Article V is essential for understanding American constitutional politics. Because formal amendment is so difficult, a great deal of constitutional change happens through judicial interpretation rather than textual revision. How courts read the Constitution — and who appoints the judges doing that reading — carries enormous weight precisely because changing the text through Article V is so demanding.