When the debate concludes, or when the Closure is invoked, the motion in question is put to a vote. The House first votes by voice vote; the Speaker or Deputy Speaker puts the question, and Members respond either "Aye!" (in favour of the motion) or "No!" (against the motion).
The presiding officer then announces the result of the voice vote, but if his or her assessment is challenged by any member or the voice vote is unclear, a recorded vote known as a
division follows. The presiding officer, if he or she believes that the result of the voice vote is clear, may reject the challenge. When a division occurs, members enter one of two lobbies (the "Aye" lobby or the "No" lobby) on either side of the Chamber, where their names are recorded by clerks. A member who wishes to pointedly abstain from a vote may do so by entering both lobbies, casting one vote for and one against. At each lobby are two tellers (themselves members of the House) who count the votes of the members.
Once the division concludes, the tellers provide the results to the presiding officer, who then announces them to the House. If there is an equality of votes, the Speaker or Deputy Speaker has a
casting vote. Traditionally, this casting vote is exercised to allow further debate, if this is possible, or otherwise to avoid a decision being taken without a majority (e.g. voting 'No' to a motion or the third reading of a bill). Ties rarely occur—the last one was in July 1993. The quorum of the House of Commons is 40 members for any vote, including the Speaker and four tellers. If fewer than 40 members have participated, the division is invalid.
