A quorum call or call to quorum is a parliamentary procedure used to delay a vote or otherwise slow down the deliberations of a parliamentary body. Since attendance at debates is not mandatory in most legislatures, it is often the case that a quorum of members is not present while debate is ongoing. In many bodies, motions such as amendments, tabling, and recommitment may be approved in the absence of a quorum, provided no member then present objects. A member wishing to delay proceedings (for example, to allow other members time to get to the chamber in order to join debate) may request that the presiding officer determine whether a quorum is present. If a quorum does not appear to be present, debate is suspended.

What happens after debate stops depends on the legislature in question. In the United States Congress, bells are rung in the various congressional office buildings to indicate to members that their presence is required in their respective chambers. Members of the House use the same electronic system as is used for voting to register their presence; in the Senate, one of the clerks will read out a roll call of Senators, who indicate their presence when called. Because of differences in procedure between the two bodies, quorum calls in the House are fairly rare, but they are quite common in the Senate. In both houses, while quorum calls officially last fifteen minutes, the actual amount of time given is at the discretion of the presiding officer.

A motion to adjourn for lack of quorum may be raised after the quorum call if an insufficient number of members present themselves.