Constituency Boundaries

Constituency Boundaries is a tool for exploring the impact of proposed changes to Parliamentary constituency boundaries. This site uses cookies to measure traffic.

Click on a nation or region below to see the current and proposed constituency boundaries and the underlying wards in each region. Please note that the full boundary data has been simplified for online use and may not correspond to the precise position of the actual boundaries at the smallest scales.

Final Proposals: 2018

The maps below show the final proposals for new constituencies, which were published in September 2018.

Revised Proposals: 2017

The maps below show the second set of proposed constituencies, which were published in October 2017 and January 2018.

Provisional Proposals: 2016

These maps show the first set of proposed constituencies, which were published in September and October 2016. These proposals have been superseded by the 2017 proposals.

How it works

Each map shows boundaries for three sets of areas: the current Parliamentary constituencies (pink), the proposed Parliamentary constituencies (blue), and the electoral wards in 2015 (black). Each of these boundaries can be toggled on and off using the checkboxes at the bottom right of the map.

The Area Information box shows information about areas in the topmost layer shown on the map: their name, code, and Parliamentary electorate in December 2015 is shown when the mouse highlights an area by hovering over it. Press and hold on an area to get the same information on a touchscreen device. By default, the wards are the topmost layer, but any layer can be brought to the top by toggling it.

Ward areas are special in that a set of wards can be selected by clicking on them, and the sum of the electorates in the selected wards is shown in the Electorate box at the top right of the map. This allows you to explore the impact of adding or removing certain wards from current or proposed constituencies. The data for the selected wards can then be downloaded by clicking Get Data. Note that on these maps the wards are shown whole and in some cases constituency boundaries cross wards.

Further information

The boundaries for the proposed constituencies shown on this website have been kindly provided by the Boundary Commissions for England, Wales, Scotland and Northern Ireland. We would like to say thank you to the Boundary Commissions for all the help they have given us in getting this data online as quickly as possible.

Further information on the boundaries and electorates of the proposed constituencies is available from the websites of the Boundary Commissions for England, Wales, Scotland, and Northern Ireland.

Further information on the boundary review process can be found in the followings House of Commons Library briefings:

Data on the boundaries of constituencies and wards contain Ordnance Survey data © Crown copyright and database right 2016. Boundary data for Great Britain is available from the Office for National Statistics Open Geography Portal. Boundary data for Northern Ireland is available from Open Data Northern Ireland. Data is licensed under the Open Government Licence v.3.0.

The map layer uses data from OpenStreetMap and tiles from Mapbox. The application uses the Leaflet JavaScript library and the SQLite database.

Developed by Oliver Hawkins for the House of Commons Library.