<P> Thirty - three amendments to the United States Constitution have been approved by the Congress and sent to the states for ratification . Twenty - seven of these amendments have been ratified and are now part of the Constitution . The first ten amendments were adopted and ratified simultaneously and are known collectively as the Bill of Rights . Six amendments adopted by Congress and sent to the states have not been ratified by the required number of states and are not part of the Constitution . Four of these amendments are still technically open and pending, one is closed and has failed by its own terms, and one is closed and has failed by the terms of the resolution proposing it . All totaled, approximately 11,539 measures to amend the Constitution have been proposed in Congress since 1789 (through December 16, 2014). </P> <P> Article V provides two methods for amending the nation's frame of government . The first method authorizes Congress, "whenever two - thirds of both houses shall deem it necessary" (a two - thirds of those members present--assuming that a quorum exists at the time that the vote is cast--and not necessarily a two - thirds vote of the entire membership elected and serving in the two houses of Congress), to propose Constitutional amendments . The second method requires Congress, "on the application of the legislatures of two - thirds of the several states" (presently 34), to "call a convention for proposing amendments". </P> <P> When the 1st Congress considered a series of constitutional amendments, it was suggested that the two houses first adopt a resolution indicating that they deemed amendments necessary . This procedure was not used . Instead, both the House and the Senate proceeded directly to consideration of a joint resolution, thereby implying that both bodies deemed amendments to be necessary . Also, when initially proposed by James Madison, the amendments were designed to be interwoven into the relevant sections of the original document . Instead, they were approved by Congress and sent to the states for ratification as supplemental additions (codicils) appended to it . Both these precedents have been followed ever since . </P> <P> Regarding the amendment process crafted during the 1787 Constitutional Convention, Madison, in The Federalist No. 43, wrote: </P>

To propose an amendment to the u.s. constitution congress would have to pass a