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After a new Bill has passed its Second reading, it moves to the comittee stage, where it is discussed in detail, usually by a Standing committee, but occasionally by a Committee of the whole house. In either case the purpose is to examine the clauses of the Bill in detail and, if necessary, to propose ammendments. In practice, the usual Government majority in both standing committees and Committees of the Whole House means that ammendments are unlikely to be accepted if opposed by the Government. Thus the direct effect of the committee stage is generally minor. However, the indirect effect can be significant, as the proposers of the Bill may use the comments raised in committee to move their own ammendments at a later stage.

Occasionally a Bill may be considered by a Select committee.