Adding an amendment to the U.S. Constitution takes two steps: Congress proposes the amendment by a two-thirds vote in both the House and the Senate, and then three-fourths of the states, currently 38 of 50, ratify it. That is how a constitutional amendment is proposed and ratified, and it is the only path that has ever worked. Article V also allows the states themselves to trigger a proposing convention, but that route has never been used. Since 1789, thousands of amendments have been introduced and only 27 have made it through.
Proposal by Congress
Both chambers of Congress must pass a joint resolution containing the proposed amendment by a two-thirds vote. That threshold is two-thirds of the members present and voting, assuming a quorum, not two-thirds of total membership.1Constitution Annotated. Article V – Amending the Constitution With every seat filled, that works out to 290 votes in the House and 67 in the Senate, though the actual number needed on any given day depends on attendance.
Once both chambers pass the resolution, it goes directly to the states. It does not go to the President, and the President cannot veto it. The Supreme Court settled this in Hollingsworth v. Virginia in 1798, where Justice Samuel Chase stated during oral argument that the President “has nothing to do with the proposition, or adoption, of amendments to the Constitution.”2Legal Information Institute. Role of the President in Proposing an Amendment The power to change the Constitution belongs to Congress and the states.
The Convention Route the Country Has Never Used
Article V provides a second way to propose amendments. Two-thirds of state legislatures, currently 34, can apply to Congress to call a national convention for proposing amendments.3National Archives. Article V, U.S. Constitution No such convention has ever been called.
Big procedural questions remain open. There is no established process for determining whether state applications address the same subject, whether old applications expire, or whether Congress has any discretion in evaluating them.4Legal Information Institute. Proposals by Convention Congress has never built a formal system for counting the applications it receives; the Secretary of the Senate and the Clerk of the House handle them as routine correspondence.
Legal scholars are also divided on whether a convention could be limited to a single topic once it convened, or whether delegates could propose changes to any part of the Constitution regardless of what the states asked for. The question has never been tested, and that uncertainty has itself acted as a brake on the process. Even so, whatever comes out of a convention still has to be ratified the same way as an amendment proposed by Congress.
Ratification by Three-Fourths of the States
However an amendment is proposed, it needs approval from three-fourths of the states to become part of the Constitution. With 50 states, that is 38.5National Archives. Constitutional Amendment Process Congress chooses which of two ratification methods the states will use: a vote by each state’s legislature, or specially elected ratifying conventions in each state.6Legal Information Institute. Choosing a Mode of Ratification
State legislatures have ratified 26 of the 27 existing amendments.6Legal Information Institute. Choosing a Mode of Ratification The convention method has been used exactly once, for the Twenty-First Amendment repealing Prohibition in 1933.7Legal Information Institute. Ratification of the Twenty-First Amendment
An amendment becomes part of the Constitution the moment the 38th state ratifies, not when federal paperwork catches up. In 1992, the Office of Legal Counsel advised that the Twenty-Seventh Amendment “became part of the Constitution once the Archivist of the United States certified that the requisite number of states had ratified the amendment.”8Legal Information Institute. Congressional Deadlines for Ratification of an Amendment Certification confirms a fact that has already occurred.
How Long States Have to Ratify
The Constitution says nothing about a time limit. Congress began attaching one with the Eighteenth Amendment in 1917, setting a seven-year deadline. The Supreme Court upheld the practice in Dillon v. Gloss in 1921, ruling that Congress’s power to choose the mode of ratification carried with it the authority to set a reasonable time limit.9Legal Information Institute. Dillon v. Gloss, 256 U.S. 368 (1921) Seven years has become the standard, though Congress can choose a different window, or none at all.
Where Congress writes the deadline matters. Some amendments include it in the amendment text itself; others put it only in the proposing resolution. Whether a deadline in the resolution carries the same legal weight as one embedded in the amendment is an unsettled question.10Constitution Annotated. Congressional Deadlines for Ratification of an Amendment
When there is no deadline, ratification can span an extraordinary stretch of time. The Twenty-Seventh Amendment, which bars Congress from giving itself a mid-term pay raise, was proposed in 1789 as part of the original Bill of Rights package. Michigan became the 38th state to ratify it on May 7, 1992, more than 202 years later.8Legal Information Institute. Congressional Deadlines for Ratification of an Amendment
Can a State Change Its Vote?
States have tried to both reverse rejections and take back approvals, and the two situations are treated differently.
A state that first votes against an amendment can later reverse course and ratify it. Congress has consistently counted these late ratifications as valid, and prior rejection carries no lasting legal weight.11Legal Information Institute. Effect of Prior Rejection of an Amendment or Rescission of Ratification
Rescission is more contentious. During the ratification of the Fourteenth Amendment, New Jersey and Ohio tried to withdraw their earlier approval, and Congress counted their ratifications anyway. In Coleman v. Miller in 1939, the Supreme Court indicated that whether a state can rescind ratification is a political question for Congress to resolve, not a matter for the courts.12Justia. Coleman v. Miller, 307 U.S. 433 (1939) Historically, once a state ratifies, Congress has treated that vote as final.
The Equal Rights Amendment has kept this question alive. Five states attempted to rescind their ERA ratifications in the 1970s. Three additional states ratified decades later, bringing the total to 38, but the Archivist has refused to certify the amendment, citing Department of Justice opinions that the congressionally imposed deadline had expired.13National Archives. Statement on the Equal Rights Amendment Ratification Process The legal status of those rescissions remains unresolved.
Certification by the Archivist
Once 38 states have ratified, the process moves to the National Archives. Under 1 U.S.C. 106b, the Archivist of the United States administers the ratification process. Each state sends the Archivist an original or certified copy of its ratification action, and the Office of the Federal Register reviews the documents for legal sufficiency and a proper authenticating signature.5National Archives. Constitutional Amendment Process
When the required number of ratifications is confirmed, the Office of the Federal Register drafts a formal proclamation for the Archivist to sign. The certification is then published in the Federal Register and the U.S. Statutes at Large. The statute directs the Archivist to publish the amendment with a certificate specifying which states ratified and confirming that it “has become valid, to all intents and purposes, as a part of the Constitution.”14Office of the Law Revision Counsel. 1 USC 106b In practice, the ERA dispute has shown that the Archivist may decline to certify when unresolved legal obstacles exist, such as an expired ratification deadline.
The One Thing That Cannot Be Amended
Article V places limits on the amendment power itself. Two original restrictions protected founding-era compromises on the slave trade and certain direct taxes until 1808, and those deadlines have long expired.15Constitution Annotated. Unamendable Subjects
One restriction remains permanently in force: no state can be stripped of its equal representation in the Senate without that state’s own consent.3National Archives. Article V, U.S. Constitution The two-senators-per-state structure could only be changed for a particular state if that state agreed. For practical purposes, it is the one feature of the Constitution beyond the reach of the amendment process described above.