The United Kingdom constitution – a mapping exercise
A briefing paper which "maps" (or summarises) the main elements of the United Kingdom's uncodified constitution.

Most UK governments are based on the MPs of the government’s party filling a majority of the seats in the House of Commons, and forming a government is relatively straightforward. When no single party holds a majority of seats, this is known as a hung parliament.
What happens after an indecisive election result? (627 KB , PDF)
There are a number of options for formation of Government following an indecisive election result. These could range from a full, formal coalition (as in 2010) to a confidence and supply arrangement (as in 2017) or a more informal arrangement.The formation will follow certain conventions and rules, and there are restrictions on government activity until a new administration is set up.
The conventions on government formation are set out in Chapter 2 of the Cabinet Manual. Where no party has a majority, and until a new Prime Minister is appointed by the Queen, the incumbent Prime Minister remains in office. The Cabinet Manual states that the incumbent should resign if and when it becomes clear that they cannot command a majority of the House of Commons and there is a clear alternative government. There is no legal requirement for government formation to take place within a set number of days.
The Manual has been subject to some criticism over a lack of clarity about the rules regarding caretaker governments (the period between a general election and the formation of a new administration). There has also been some discussion of whether the date that Parliament meets for the first time following an election should be put on a statutory basis, rather than continue as a prerogative power, and whether it should be brought forward or be pushed back in the event of a hung parliament.
Historical information about hung parliaments, coalition agreements, and confidence and supply arrangements is available in the Library briefing Hung Parliaments. Details about the operation of the 2010 Conservative – Liberal Democrat Coalition Government are set out in the Library briefing the 2010 Coalition Government at Westminster. Details on the confidence and supply arrangement between the Conservative and Democratic Unionist parties can be found in the library briefing paper The 2017 Government at Westminster: Governing as a minority.
What happens after an indecisive election result? (627 KB , PDF)
A briefing paper which "maps" (or summarises) the main elements of the United Kingdom's uncodified constitution.
On Wednesday 25 June 2025, there will be an Estimates Day debate on the spending of the Ministry of Justice. This debate pack contains details of the latest estimates and previous expenditure, background material, and suggestions for further reading.
A briefing paper on the office and functions of the Prime Minister