Cloture is the Senate's formal mechanism for ending unlimited debate on a measure and bringing it to a final vote. Under Senate Rule XXII, invoking cloture on most legislation requires the affirmative votes of three-fifths of all senators duly chosen and sworn — 60 votes when the Senate has 100 members. If cloture fails, debate continues indefinitely, and the Majority Leader typically pulls the bill from the floor rather than allow it to stall indefinitely.
The 60-vote threshold for cloture is the functional basis of what's often called the Senate's "60-vote rule" — the practical requirement that most significant legislation needs 60 senators to pass, not just 51.
The Mechanics of a Cloture Vote
To invoke cloture, at least 16 senators must sign a cloture motion and present it to the Senate. After the motion is filed, there is a mandatory one-day intervening business before the cloture vote can occur. When the vote happens, three-fifths of all senators who have been chosen and sworn — not three-fifths of those present and voting — must vote "aye." Vacancies reduce the required number proportionally.
If cloture is invoked, debate is limited to 30 more hours on the measure (the 30 hours can be waived by unanimous consent or a three-fifths vote). After those 30 hours, a vote on final passage must occur.
If cloture fails, the Majority Leader must decide whether to try again — sometimes bringing a second cloture vote if they believe they can peel off additional votes — or pull the bill from the floor. Failed cloture doesn't kill the bill permanently; it can be brought back at any time, sometimes weeks or months later when political circumstances change.
Why Senators Vote for Cloture Against Their Own Position on the Bill
A vote for cloture is a vote to allow a final vote, not a vote for the bill itself. This distinction is procedurally meaningful: a senator might believe the underlying bill should be defeated but still vote for cloture to allow the Senate to conduct business. Majority leaders sometimes negotiate process votes separately from policy votes — securing agreement to debate something without securing agreement on the outcome.
The inverse also happens: a senator might support the bill substantively but vote against cloture to protest the lack of amendment opportunities, the procedural conditions attached to the measure, or the Majority Leader's overall scheduling choices. Cloture votes sometimes reveal cross-cutting coalitions that don't neatly map onto support for the underlying legislation.
Cloture on Nominations: The Simple Majority Exception
In 2013, the Senate Democratic majority changed its rules — through a simple majority vote, the "nuclear option" — to require only a simple majority (51 votes) to invoke cloture on executive branch nominations and lower federal court nominations. In 2017, the Senate Republican majority extended this change to Supreme Court nominations. All judicial and executive nominations now require only 51 votes to advance.
The original 60-vote cloture threshold remains in place for legislation. The distinction between nominations and legislation is now one of the sharpest procedural asymmetries in the Senate: a simple majority can confirm a Supreme Court Justice or a Cabinet secretary, but that same majority cannot pass most legislation without 60 votes to cut off debate.
Cloture's Growth Over Time
Cloture was used rarely for most of the 20th century. In the 1960s and 1970s, the Senate filed a handful of cloture motions per year. By the 2010s, cloture was being filed on virtually every major piece of legislation, and sometimes multiple times on the same bill. The most cloture motions filed in any single Congress since the rule was adopted in 1917 is 336, in the 117th Congress (2021–2022). The frequency reflects the procedural arms race between majorities seeking to advance their agenda and minorities using every available tool to slow them down.