There are two types of constitutional convention. State ratifying conventions, which you are correct is the way that the 21st amendment was ratified by the sta

There are two types of constitutional convention. State ratifying conventions, which you are correct is the way that the 21st amendment was ratified by the states after having received a two thirds majority in congress: https://en.wikipedia.org/wiki/State_ratifying_conventions https://en.wikipedia.org/wiki/State_ratifying_conventions Article V conventions, which replace the legislature stage but then need to be ratified by the states either by the legislatures or by a state ratifying convention: https://en.wikipedia.org/wiki/Convention_to_propose_amendments_to_the_United_States_Constitution https://en.wikipedia.org/wiki/Convention_to_propose_amendmen... the latter has never happened and the constitution is very vague about what they would entail, and I think is what the earlier poster was referencing (there has been some recent noise around them) this graphic is quite helpful: https://en.wikipedia.org/wiki/State_ratifying_conventions#/media/File:Constitutional_amendment_process_(USA).png https://en.wikipedia.org/wiki/State_ratifying_conventions#/m...