VoteUK - Some Minor Setbacks

One of the problems with creating a service which deals with elections, is that boundaries change.  One year you might be in the Electoral Constituency of Woking, the next year it might be Guildford.  Boundaries have to shift in order to keep each MP with roughly the same number of constituents.

The work to determine how these boundaries should be formed is done by The Boundary Commission.  They have produced a report to show how the boundaries will be set out at the next General Election.  There report - while detailed, thorough and no doubt accurate - is utterly useless.  Well, from a "linked data" perspective.  It's a 57 MB PDF if you want to see for your self.

I was expecting, along with the rationales, maps and population densities to see something like

Constituency: Woking

Ward: Mount Herman East

Postcodes: GU22 0XX, GU22 0XY, GU22 0XZ ...

Or, indeed, anything which would allow one to easily link the data to other sources.  This is what the report contains.

A Detailed Map of Surrey

A Detailed Map of Surrey

While the map is pretty detailed, it doesn't contain any geo-spatial co-ordinates.  It looks like it has just been drawn by hand in ink.  There is no way to extract any information out of this map.

The also produce a list of constituencies and wards.

This is not text - it's a screen shot!

This is not text - it's a screen shot!

There are three problems with this.

  1. It's a screen shot.  I don't mean that I've taken a screen shot, I mean that they have taken a screenshot of the text and pasted it into the report.  There is no way to copy the text out of there.
  2. Even if it were possible, they don't list the Government standard codes for the wards
  3. There are no postcodes or other forms of information which tie the ward to a specific place.


So, how can I find this information?  I know! I'll write to those nice folk at Parliament

Dear Sir or Madam,

I notice that you provide a website which allows Constituency lookup from a postcode (

Do you have the data for the *new* Constituencies proposed by the Boundary Commission?

The Boundary Commission has maps of the new areas ( but these don't have postcodes on them.

I'm happy to make an FoI request if that is your preferred way of releasing the information.

If you do not have the information - would you be able to tell me who does?

Many thanks

A few days later I got back this.

Dear Sir,

Thank you for your enquiry asking if we have the post codes for the new Constituencies proposed by the Boundary Commission.

I am afraid, the House of Commons Information Office is unable to give you a list of the post codes for the proposed "new" constituencies Boundaries  .The House purchases a list of postcodes for each Parliamentary constituencies from the Office of National Statistics and the new list will not be purchased until nearer the time of the General Election when the changes in Parliamentary constituencies take effect.

You may like to contact the Office of National Statistic to see if you can purchase a list from them of the new constituencies.

Customer Contact Centre
Office for National Statistics
Room 1.015
Government Buildings
Cardiff Road
South Wales
NP10 8XG
Telephone - +44 (0) 845 601 3034

I hope this is helpful

So, off to the ONS! I took a look through their website, couldn't find what I wanted, so I emailed them.

I'm looking for some definitive data on the electoral constituencies and their comprising wards for the next general election.  That is, those incorporating the boundary changes in the Boundary Commission's Fifth periodical report.

Under "Names and codes for Electoral Geography" your document "Westminster Parliamentary Constituencies" only lists the 647 constituencies from the 2005 election.  Do you have the data for the upcoming election?

Similarly, in "Names and codes for Administrative Geography" I'm not sure if the document "Wards (Eng) Dec 2008 Names and Codes" contains the latest wards.  There also seems to be no schema to link Wards to Constituencies that I can see.

Do you hold such information?

Which sadly got back

Dear Terence,
Thank you for your recent enquiry
Please be advised that this information is currently not available. This is because current wards are split across the new boundaries and a review of these is about to be carried out which makes them subject to change.

If you have any further questions, please let me know.

So, no luck there.

Is this really so hard? All I want is to know that Postcode X is in Ward Y of Constituency Z.  It would appear that this information just isn't held anywhere. The review has been completed by the Boundary Commission but they either don't consider linked data or they don't share it. I just wish they would Set Our Data Free.

Or am I barking up the wrong tree entirely?

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2 thoughts on “VoteUK - Some Minor Setbacks”

  1. Hi, I'm currently responsible for making sure WriteToThem/TheyWorkForYou gives you the right wards, constituencies, etc. so I'm sadly quite knowledgeable in this area. 🙂

    Westminster constituency make-up is based upon ward boundaries at a particular date when they start the boundary review - ward boundaries can then of course change after that point, so you can't build up a Westminster constituency boundary from ward boundaries unless you're certain the ward boundaries haven't changed (and even then, I feel a little scared in doing so in case I've missed something). You can get a full list of the ward mapping to constituencies (it's been amended since, see below) at - it's the wards as they were in April 2005.

    The vector data of boundaries is available from Ordnance Survey, it's called Boundary-Line and costs £914 for Great Britain (Northern Ireland mySociety had to do manually - see the tortuous code in the codebase) - - and includes future boundaries (it's unclear if they've incorporated the latest amendment to the boundaries, see below).

    OS's OpenSpace project at allows you to fetch/plot administrative boundaries, up to 1000 requests in a 24-hour period - it doesn't look like they've made future boundaries available, though.

    Making this data freely available (which seems pretty fundamental in a democracy), has been requested twice on OPSI's Unlocking Service, once by me:

    Your best bet is probably if we are able to add to TheyWorkForYou's API the facility to fetch for a postcode the constituency as it will be at the next general election, as well as the current constituency. Given e.g. the user guide for the latest issue of Boundary-Line (available from OS's website above) don't mention the following SI change to the boundaries: - I'm not sure this can be done other than manually from the SIs, which is the situation we were in at the time of the Scottish boundary changes at the 2005 election...

    1. Thanks for the detailed reply. I currently use getConstituency from TWFY to power
      I must admit, it would be lovely to be able to get ward data as well via the API.

      What staggers me is that the information genuinely doesn't seem to be held in any one location. Given that a General Election could be called at any point - surely it makes sense to have everything ready on the off-chance that the PM calls an election.

      I spoke to OS who said that they didn't have the data for the latest changes. They also suggested that they weren't the cheapest place to buy the data from - some of the partners are more geared to selling to small / independent users.

      All a bit depressing 🙁

      I'm unsure how your codebase works, but all the data for contacting local councils is on my FoI request.
      Do let me know if there's anything I can do to help MySociety integrate some of this data into the codebase.


What are your reckons?

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