What does devolution mean and how does it work across the UK?

Millions of voters will head to the polls on 7 May, for local elections in England and national parliamentary elections in Scotland and Wales.

The UK has had devolved governments since the late 1990s, which work alongside the Westminster Parliament.

There are different types of devolution in place across Scotland, Wales and Northern Ireland, as well as in parts of England.

Devolution means the transfer of power away from central government.

For many years, England, Wales, Scotland and Northern Ireland were run by the UK parliament, based in Westminster in London.

However, there were growing demands for greater economic, social and political freedom.

This led to public votes about devolution in Scotland and Wales in 1997, and on both sides of the Northern Irish/Irish border in 1998 as part of the Good Friday Agreement.

This led to the creation of three elected institutions:

• the Scottish Parliament, in 1999
• the National Assembly for Wales (now called the Senedd), in 1999
• the Northern Ireland Assembly, in 1998

A number of mayoral posts have also been introduced in England, with varying powers and responsibilities.

The UK government in Westminster remains responsible for policies which affect only England.

It is also responsible for overall UK policy in a number of areas.

These include:

• defence and national security
• foreign policy
• immigration
• citizenship
• tax - although Scotland, Wales and Northern Ireland have some tax-raising powers

The Scottish Parliament sits at Holyrood in Edinburgh. There are 129 elected Members of the Scottish Parliament (MSPs).

Scotland already had its own legal and education system. After devolution, it became responsible for many other areas, including:

• agriculture, forestry and fishing
• education
• environment
• fire services
• health
• housing
• justice, policing and courts
• local government and planning
• some transport
• taxes including income tax, stamp duty and air passenger duty
• tourism
• some welfare powers

Its powers were extended in 2012, after the 2014 referendum on whether Scotland should become independent, and again in 2016 through the Scotland Act.

The Scottish National Party (SNP), which has formed the Scottish government at Holyrood since 2007, continues to argue for full independence.

Since May 2020, the National Assembly of Wales has been known as the Senedd Cymru (Welsh Parliament).

It meets in Cardiff Bay, and is currently made up of 60 elected Members of the Senedd (MS).

Following the creation of 16 new constituencies, the number of members will rise to 96 after the 7 May election.

The Senedd's responsibilities include:

• agriculture, forestry and fishing
• education
• environment
• health and social care
• housing
• local government
• highways and transport
• some control over income tax, stamp duty and landfill tax
• Welsh language
• tourism

The Northern Ireland Assembly sits at Stormont in Belfast. There are 90 elected Members of the Legislative Assembly (MLAs).

The Northern Ireland Executive consists of nine government departments, each responsible for specific areas of policy and public services.

Devolution in Northern Ireland is different to Scotland and Wales, with government powers divided into three categories:

• transferred powers which are controlled by the Northern Ireland Assembly
• reserved powers which remain with Westminster, but could be transferred in the future if the Northern Ireland Executive wants them. These include prisons and civil defence
• excepted powers which cannot be moved to Stormont without special laws being made in Westminster. These include elections and national defence

The assembly's main powers include:

• agriculture
• education
• environment and planning
• health and social services
• local government
• justice, policing and prisons
• control over air passenger duty
• transport
• culture, language and sport

The power-sharing agreement between the nationalist and unionist communities in Northern Ireland is also key.

The first minister and deputy first minister - one representing each of the two largest parties in power - jointly lead the government in a mandatory coalition. Despite different job titles, they have the same powers.

Since its establishment in 1998, the Northern Ireland Assembly has been suspended a number of times.

Most recently, in February 2022, the DUP withdrew from the power-sharing coalition in protest against post-Brexit trade agreements. Two years later, devolved government was restored when the DUP agreed to return after a new trade deal was reached with Westminster.

Since the late 1990s, more powers have also been given to local and regional mayors in England, covering policy areas such as transport and housing.

The Mayor of London was the first role of this kind, created alongside the London Assembly after a referendum in 1998.

The London mayor decides how much money to spend and sets priorities in some key areas.

They can set bus and Tube fares, and decide targets for the number of affordable homes.

There are a number of other directly-elected mayors across England, with varying powers:

• 15 local authority mayors who typically have the same powers as local authorities, which have a council leader instead of a mayor (with some exceptions)
• 13 metro mayors (not including the Mayor of London) who are responsible for areas including multiple local councils. They can set out plans to boost their local economy and have some powers over housing and transport

Elections to select new mayors in Cumbria and Cheshire & Warrington have been postponed until 2027. Polls to pick new mayors in Greater Essex, Norfolk and Suffolk, Hampshire and the Solent, and Sussex and Brighton, have been pushed back until May 2028.

Local authorities in Scotland and Northern Ireland are not covered by the legislation that introduced the different types of elected mayors in England and Wales.

Shortly after his election in July 2024, Prime Minister Sir Keir Starmer said his government would let "those with skin in the game - those that know their communities - make much better decisions".

The government subsequently introduced its English Devolution and Community Empowerment Bill to deliver its manifesto commitment to:

• further decentralise power from central government
• transfer more powers to local government
• increase mayoral powers

The government wants all areas of England to be covered by new "strategic authorities" led by a mayor. These mayors will have the ability to act in a number of areas, including:

• transport
• housing
• environment
• public safety
• health and public service reform
• employment

The bill is in its final stages going through Parliament.

It is due to pass before the end of the current parliamentary session, which must happen before the State Opening of Parliament on 13 May.

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