By-election timetables
This briefing explains the timetable for by-elections to the UK Parliament
A general election must be called at some time in 2024 and the latest date an election can be held is 28 January 2025
General election timetables 2024 (360 KB , Excel Spreadsheet)
Elections are held using a timetable. This sets out when the election formally starts and when polling day must be. For a general election to the UK Parliament, the formal timetable starts with the dissolution of Parliament and ends with polling day.
The table below sets out the dissolution date and the corresponding polling day for each Thursday until the last possible polling day for the next general election. Earlier polling dates not on a Thursday can be found in the Excel worksheet, All possible polling dates.
Dissolution is the official term for the end of a Parliament. At dissolution all the business in both Houses comes to an end and all MPs lose their seats in the House of Commons. Dissolution is deemed to have occurred just after midnight at the start of the day. Dissolution triggers the issuing of new writs to elect new members of Parliament.
Parliament is dissolved by the King, using prerogative powers. By convention, these powers are exercised following a request from the Prime Minister. If the Prime Minster does not request an earlier dissolution, Parliament will automatically be dissolved at the beginning of the fifth anniversary of the day on which it first met.
The dissolution of Parliament and the date of meeting of the new Parliament are determined by Royal Proclamation. See section 4.3 of Commons Library briefing The royal prerogative and ministerial advice for more information on prerogative powers.
The 2019 Parliament first met on 17 December 2019. If no early election is called, the 2019 Parliament will automatically dissolve just after midnight on 17 December 2024.
Writs are legal documents which authorise a general election. A writ is issued for each constituency and sent to the relevant returning officer.
For a UK Parliament general election, the timetable is 25 working days.
The timetable is set out in the Parliamentary Elections Rules in Schedule 1 of the Representation of the People Act 1983, as amended.
Weekends, bank holidays and Christmas Eve are not counted in the election timetable. If there is a bank holiday in the period chosen for the election, then dissolution is earlier to ensure polling day is on the correct day. A bank holiday in one part of the UK is disregarded in the whole of the UK. This prevents polling day being on different days in different parts of the UK.
Deadlines for electoral registration and for postal and proxy voting are not contained in the election timetable set out in Schedule 1 of the 1983 Act. They are contained in separate registration regulations. There are separate sets of regulations for the three legal jurisdictions of the UK. See Commons Library briefing Absent voting for more information.
If Parliament automatically dissolves on 17 December 2024, then polling day will be Tuesday 28 January 2025.
General elections are held on Thursday by tradition, but they can be held on any weekday. Dissolution is normally timed to provide for polling day on a Thursday. The last Thursday that a general election can be held is 23 January 2025.
The last general election not to be held on a Thursday, was Tuesday 27 October 1931.
If the King dissolves Parliament before 17 December 2024 at the request of the Prime Minister, an announcement will be made before dissolution.
This will give time for a Royal Proclamation to be issued stating when dissolution will occur. Dissolution will be timed to allow for polling day to occur on the Prime Minister’s chosen date.
It also allows for Parliament to conduct what is known as ‘wash-up’. The wash-up period is when both Houses of Parliament complete any necessary business. Any unfinished business is lost at dissolution and the Government may need the cooperation of the Opposition in passing legislation that is still in progress.
The worksheets in the attached Excel spreadsheet show:
To use the underlying data, take a date for dissolution and work down from ‘day 0’ to ‘day 25’ taking the day of the week from the first column. For ease of use, the dissolution date and polling date are given in rows 1 and 2.
As noted above, weekends, UK bank holidays, and Christmas Eve are excluded from these calculations as they are not counted in the election timetable.
General election timetables 2024 (360 KB , Excel Spreadsheet)
This briefing explains the timetable for by-elections to the UK Parliament
Full results and analysis of the 4th July 2024 general election, where Labour won a majority in Parliament
Turnout at the 2024 general election was below 2019 levels across the UK. Seats won by Labour generally had lower turnout than seats won by the Conservatives.