Formal amendments may be ratified by

The Congress, whenever two thirds of both Houses shall deem it necessary, shall propose Amendments to this Constitution, or, on the Application of the Legislatures of two thirds of the several States, shall call a Convention for proposing Amendments, which, in either Case, shall be valid to all Intents and Purposes, as Part of this Constitution, when ratified by the Legislatures of three fourths of the several States, or by Conventions in three fourths thereof, as the one or the other Mode of Ratification may be proposed by the Congress; Provided that no Amendment which may be made prior to the Year One thousand eight hundred and eight shall in any Manner affect the first and fourth Clauses in the Ninth Section of the first Article; and that no State, without its Consent, shall be deprived of its equal Suffrage in the Senate.

Article V sets forth procedures for amending the Constitution.1 Footnote
U.S. Const. art. V . This essay does not examine whether Article V provides the exclusive procedures for amending the Constitution. See generally, e.g., Akhil Reed Amar , The Consent of the Governed: Constitutional Amendment Outside Article V , 94 Colum. L. Rev. 457 , 458–59 (1994) (arguing that the people of the United States may amend the Constitution using methods not specifically outlined in Article V). Most of the Article’s text addresses the proposal and ratification of amendments.2 Footnote
U.S. Const. art. V . Two sentences at the end of the Article make certain subjects unamendable.3 Footnote
Id. ( “Provided that no Amendment which may be made prior to the Year One thousand eight hundred and eight shall in any Manner affect the first and fourth Clauses in the Ninth Section of the first Article; and that no State, without its Consent, shall be deprived of its equal Suffrage in the Senate.” ). Since the Founding, Congress has used Article V’s procedures to propose thirty-three constitutional amendments.4 Footnote
For a list of the twenty-seven amendments the states ratified, see Intro.3.1 Ratification of Amendments to the Constitution Generally. For a list of the six constitutional amendments that Congress proposed but the states have not ratified, see Intro.3.7 Proposed Amendments Not Ratified by the States. The states have ratified twenty-seven of these proposed amendments, which include the first ten amendments, known as the Bill of Rights,5 Footnote
The Bill of Rights safeguards certain individual rights from government interference. For a discussion of the proposal and ratification of the Bill of Rights, see Intro.3.2 Bill of Rights (First Through Tenth Amendments). thereby making them part of the Constitution.

Article V establishes two methods for proposing amendments to the Constitution.6 Footnote
U.S. Const. art. V ( “The Congress, whenever two thirds of both Houses shall deem it necessary, shall propose Amendments to this Constitution, or, on the Application of the Legislatures of two thirds of the several States, shall call a Convention for proposing Amendments. . ..” ). The first method requires both the House and Senate to propose a constitutional amendment by a vote of two-thirds of the Members present.7 Footnote
Id. ; Nat’l Prohibition Cases, 253 U.S. 350, 386 (1920) ( “The two-thirds vote in each house which is required in proposing an amendment is a vote of two-thirds of the members present—assuming the presence of a quorum—and not a vote of two-thirds of the entire membership, present and absent.” ). This is the only method for proposing amendments that has been used thus far. Alternatively, Article V provides that Congress “shall” call a convention for proposing amendments upon the request of two-thirds of the state legislatures.8 Footnote
U.S. Const. art. V . This method of proposing amendments, which scholars have debated at length, has never been used.9 Footnote
See ArtV.3.3 Proposals of Amendments by Convention.

Article V also sets forth two methods for states to ratify amendments to the Constitution.10 Footnote
U.S. Const. art. V (stating that amendments to the Constitution may be ratified “by the Legislatures of three fourths of the several States, or by Conventions in three fourths thereof, as the one or the other Mode of Ratification may be proposed by the Congress” ). Congress determines which method the states must follow in order for proposed amendments to become effective.11 Footnote
United States v. Sprague, 282 U.S. 716, 730 (1931) ( “The choice . . . of the mode of ratification lies in the sole discretion of Congress.” ). The first method of ratification requires three-fourths of the state legislatures to ratify an amendment to the Constitution.12 Footnote
U.S. Const. art. V . Alternatively, Congress may require that three-fourths of state ratifying conventions approve a proposed amendment.13 Footnote
Id. Congress has specified this second mode of amendment only once, for the Twenty-First Amendment, which repealed the Eighteenth Amendment establishing Prohibition.14 Footnote
See ArtV.4.3 Ratification by Conventions. The Eighteenth Amendment prohibited “the manufacture, sale, or transportation of intoxicating liquors within, the importation thereof into, or the exportation thereof from the United States and all territory subject to the jurisdiction thereof for beverage purposes.” U.S. Const. amend. XVIII , repealed by id. amend. XXI .

The last two sentences of Article V make certain subjects unamendable.15 Footnote
Id. art. V ( “Provided that no Amendment which may be made prior to the Year One thousand eight hundred and eight shall in any Manner affect the first and fourth Clauses in the Ninth Section of the first Article; and that no State, without its Consent, shall be deprived of its equal Suffrage in the Senate.” ). The first of these sentences prohibited amendments prior to 1808 that would have affected the Constitution’s limitations on Congress’s power to (1) restrict the slave trade, or (2) levy certain taxes on land or slaves.16 Footnote
See id. See also Hylton v. United States, 3 U.S. (3 Dall.) 171, 177 (1796) (Paterson, J., concurring) (recounting Founding-era debates over these limitations on amendments). This sentence’s limitations on amendments have expired. The second sentence of Article V, which remains in effect, prohibits amendments that would deprive states, without their consent, from having equal suffrage in the Senate.17 Footnote
U.S. Const. art. V . Scholars have debated whether the last two sentences of Article V effectively prohibit (or formerly prohibited) amendments on these subjects.18 Footnote
See generally, e.g., Douglas Linder , What in the Constitution Cannot Be Amended? , 23 Ariz. L. Rev. 717 , 733 (1981) . See also ArtV.5 Unamendable Subjects.

This essay examines Article V’s procedures for amending the Constitution. It begins with an overview of the historical background of Article V. The Essay then examines relevant Supreme Court decisions, historical practices, and academic debates related to the methods that Article V establishes for proposing and ratifying constitutional amendments.

Footnotes 1 U.S. Const. art. V . This essay does not examine whether Article V provides the exclusive procedures for amending the Constitution. See generally, e.g., Akhil Reed Amar , The Consent of the Governed: Constitutional Amendment Outside Article V , 94 Colum. L. Rev. 457 , 458–59 (1994) (arguing that the people of the United States may amend the Constitution using methods not specifically outlined in Article V). 2 U.S. Const. art. V . 3 Id. ( “Provided that no Amendment which may be made prior to the Year One thousand eight hundred and eight shall in any Manner affect the first and fourth Clauses in the Ninth Section of the first Article; and that no State, without its Consent, shall be deprived of its equal Suffrage in the Senate.” ). 4 For a list of the twenty-seven amendments the states ratified, see Intro.3.1 Ratification of Amendments to the Constitution Generally. For a list of the six constitutional amendments that Congress proposed but the states have not ratified, see Intro.3.7 Proposed Amendments Not Ratified by the States. 5 The Bill of Rights safeguards certain individual rights from government interference. For a discussion of the proposal and ratification of the Bill of Rights, see Intro.3.2 Bill of Rights (First Through Tenth Amendments). 6 U.S. Const. art. V ( “The Congress, whenever two thirds of both Houses shall deem it necessary, shall propose Amendments to this Constitution, or, on the Application of the Legislatures of two thirds of the several States, shall call a Convention for proposing Amendments. . ..” ). 7 Id. ; Nat’l Prohibition Cases, 253 U.S. 350, 386 (1920) ( “The two-thirds vote in each house which is required in proposing an amendment is a vote of two-thirds of the members present—assuming the presence of a quorum—and not a vote of two-thirds of the entire membership, present and absent.” ). 8 U.S. Const. art. V . 9 See ArtV.3.3 Proposals of Amendments by Convention. 10 U.S. Const. art. V (stating that amendments to the Constitution may be ratified “by the Legislatures of three fourths of the several States, or by Conventions in three fourths thereof, as the one or the other Mode of Ratification may be proposed by the Congress” ). 11 United States v. Sprague, 282 U.S. 716, 730 (1931) ( “The choice . . . of the mode of ratification lies in the sole discretion of Congress.” ). 12 U.S. Const. art. V . 13 Id. 14 See ArtV.4.3 Ratification by Conventions. The Eighteenth Amendment prohibited “the manufacture, sale, or transportation of intoxicating liquors within, the importation thereof into, or the exportation thereof from the United States and all territory subject to the jurisdiction thereof for beverage purposes.” U.S. Const. amend. XVIII , repealed by id. amend. XXI . 15 Id. art. V ( “Provided that no Amendment which may be made prior to the Year One thousand eight hundred and eight shall in any Manner affect the first and fourth Clauses in the Ninth Section of the first Article; and that no State, without its Consent, shall be deprived of its equal Suffrage in the Senate.” ). 16 See id. See also Hylton v. United States, 3 U.S. (3 Dall.) 171, 177 (1796) (Paterson, J., concurring) (recounting Founding-era debates over these limitations on amendments). 17 U.S. Const. art. V . 18 See generally, e.g., Douglas Linder , What in the Constitution Cannot Be Amended? , 23 Ariz. L. Rev. 717 , 733 (1981) . See also ArtV.5 Unamendable Subjects.