Boundary reviews
UK Parliamentary constituency boundaries are reviewed periodically to take account of population changes. Reviews are carried out by four Boundary Commissions, one for each part of the UK.
The Commissions must follow certain rules but they also rely on public feedback to help create seats that have local support and take account of local community ties where possible. This briefing explains the public consultation process used during reviews.
The 2023 Review
The 2023 Review review was formally launched on 5 January 2021. There were several stages of public consultation. The timings are a matter for each Commission but there are some statutory provisions that they must follow. They are set out in set out in the Parliamentary Constituencies Act 1986, as amended.
The Commissions submitted their final reports to the Speaker of the House on 27 June 2023. The final recommendations were published on 28 June 2023. The Parliamentary Constituencies Order 2023, which implements the new boundaries was approved in November 2023 and the new boundaries will be used at the next general election.
The dates of the different stages of the review are summarised below.
The next review must be completed by 1 October 2031. It is likely to start in early 2029.
Consultation stages
The initial consultation period
Publishing initial proposals triggered an eight-week consultation. This stage allowed people to make written representations. Each Commission must publish all submissions received at some point after the end of the eight weeks. Publishing these triggers the secondary consultation.
The secondary consultation period
The secondary consultation period for the 2023 Review ran for six weeks and representations could include comments on submissions from the initial consultation. The 2031 Review will have an eight week secondary consultation.
The secondary period included public hearings. There must be at least two and no more than five per region of England, lasting up to two days. Scotland, Wales and Northern Ireland also had each had to at least two and no more than five hearings. They also could last up to two days.
After the secondary consultation period, each Commission must publish any written submissions and transcripts of the public hearings.
The third consultation period
If a Commission decides to publish revised proposals as a result of representations received in the first two consultation periods, this triggers a third consultation.
This lasted four weeks for the 2023 Review. The next review will have an eight week period. There are no public hearings in the third consultation
Making submissions
Anyone can make a submission during a consultation period. This includes MPs but they must make submissions the same way as everyone else.
A Commission will give equal consideration to each submission regardless of how it is submitted. This could be a presentation at a public hearing or a written submission. Written submissions can be electronic or hard copy but people are encouraged to respond via the review websites each Commission provides.
The Commissions encourage people to say whether they agree or disagree with proposals. If someone disagrees, they are encouraged to suggest alternative proposals.
The Commissions will publish more details on their websites:
Boundary Commission for England
Boundary Commission for Scotland
Boundary Commission for Northern Ireland
There is more information on the background to boundary reviews and the number of Members of Parliament in the Library briefing Constituency boundary reviews and the number of MPs (SN05929).