Parliamentary and sessional periods

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8.2A Parliament is taken to be the period between the date on which a new Parliament has met, under the terms of a proclamation made by the Queen on the advice of her Privy Council, and the date of dissolution of that Parliament under the terms of the Fixed-term Parliaments Act 2011. In 2015 and 2017 the proclamations setting the day and place of the first meeting of the new Parliament were on 30 March 2015 and 3 May 2017 respectively.

The Fixed-term Parliaments Act 2011 establishes a fixed five-year term for Parliament, with General Elections held on the first Thursday in May five years after the previous election, except in the event of an early General Election being triggered.1 In the case of an early General Election, the date of the election is set by royal proclamation and dissolution takes place 25 working days before that date. The date of the first meeting of the new Parliament is fixed by proclamation which may be issued once the previous Parliament has been dissolved.1A The Act provides two mechanisms by which an early General Election may take place. The first is where two-thirds of the whole membership of the House of Commons votes in favour of the motion ‘That there shall be an early parliamentary General Election’.2 Alternatively, an early election may arise if 14 days after resolving ‘That this House has no confidence in Her Majesty's Government’, the House of Commons fails to pass a motion ‘That this House has confidence in Her Majesty's Government’.3 The Act also provides that a General Election must take place 25 working days after Parliament is dissolved. In October 2019, the Government introduced a Bill to bypass the requirements of the Fixed-term Parliaments Act 2011 by providing for a General Election to be held on 12 December 2019, and for that day to be treated as polling day under the provisions of the 2011 Act. This two-clause Bill, requiring only a simple majority to pass,4 was introduced on 29 October and received Royal Assent on 31 October 2019 as the Early Parliamentary General Election Act 2019.5

A session is the period of time between the meeting of a Parliament, whether after a prorogation or a dissolution, and its prorogation. During the course of a session, either House may adjourn itself on its own motion to such date as it pleases. Sessions are of indeterminate length. Since the passing of the Fixed-term Parliaments Act 2011, sessions have generally run from May of one year to May of the next. Previously, sessions, with the exception of the sessions immediately before and after a dissolution, tended to run from October or November of one year to October or November of the next. The first session of both the 2010 and the 2017 Parliaments ran for two years.

The period between the prorogation of Parliament and its reassembly in a new session is termed a ‘recess’, while the period between the adjournment of either House and the resumption of its sitting is properly called an ‘adjournment’ (although in practice the word ‘recess' is generally also used in this sense). A prorogation terminates a session; an adjournment is an interruption in the course of a single session.


  1. 1. Fixed-term Parliaments Act 2011, s 1.
  2. 1A. Fixed-term Parliaments Act 2011, s 3(4).
  3. 2. This happened on 19 April 2017 when the House voted by 522 to 13 in favour of an early General Election under the terms of the 2011 Act (Votes and Proceedings, 19 April 2017).
  4. 3. Fixed-term Parliaments Act 2011, s 2.
  5. 4. In the Commons the Bill was passed without a division on Second Reading and by 438 to 20 on Third Reading. There were no divisions on the Bill in the Lords.
  6. 5. Votes and Proceedings, 31 October 2019.