Dissolution of the Parliament of the United Kingdom

The Parliament of the United Kingdom is dissolved 25 working days before a polling day as determined by the Fixed-term Parliaments Act 2011. This period was formerly 17 days, and the new 25-day period, operative for the first time in the General Election of 2015 (7 May), represents the longest United Kingdom election period without a Parliament since 1924. Importantly, the Act does not affect The Sovereign's power to prorogue Parliament, under 'Supplementary provisions' of the Act.

Members of Parliament cease to be so, as soon as it is dissolved, and they may not enter the Palace of Westminster, although they and their staff continue to be paid until polling day. Parliament is usually prorogued or adjourned before it is dissolved. Parliament may continue to sit for a wash-up period of a few days after the Prime Minister has announced the date when Parliament will be dissolved, to finish some last items of Parliamentary business.

A Royal Proclamation is made summoning a new parliament, fixing the date when the new parliament is to assemble, and requiring the despatch of writs of summons to the Lords Spiritual and Temporal. Under the Fixed-term Parliaments Act, writs of election are now despached to the returning officers of each constituency automatically, by virtue of a provision contained in the statute (in concert with the fact that the Royal Proclamation no longer summons the holding of the election, but only the meeting of the new Parliament). A general election must be held 17 days (excluding weekends and bank holidays) after the Proclamation summoning parliament issues. By tradition, a copy of the Royal Proclamation is delivered by hand from the Privy Council Office to Mansion House in the City of London. It is then read out by the Common Cryer (aka Mace-bearer or Serjeant-at-Arms) of the City on the steps of the Royal Exchange in the heart of the City, having been handed to him by the Common Serjeant of the City, ahead of its being also read out in the London boroughs. This tradition was again carried out at the most recent dissolution, in March 2015.

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