News — postcode data

The Postcode system is a continually evolving structure.

As towns are redeveloped, housing stock introduced and business centres established; Postcodes are created to accommodate new addresses or changed to keep the postal system as efficient as possible.

These changes can have significant impact on organisations who rely on Postcode related information as part of their business operations whether it is capturing correct customer addresses, planning marketing and PR campaigns or managing sales territories.

Keeping Postcode information up to date is therefore essential for many businesses which is why we source and apply the latest Postcode and Government information updates to all of our data and map products every 3 months.

For the latest September 2016 update, we wanted to quantify how many changes have occurred and also see if there are any geographical patterns in where the changes are happening.

Postcode Changes In Numbers

Following the September 2016 update, there are now 1,759,280 current Postcodes in use across the United Kingdom.

• Since the previous update in June, there have been 4,406 new Postcodes introduced to, and 3,141 Postcodes retired from, the UK Postcode system.
• The Postcode Area with the highest number of new Postcodes in the last 3 months is B (Birmingham) with 102 new Postcodes.
• The Postcode Area with the highest number of Postcodes being retired in the previous 3 months is M (Manchester) with 124 retired Postcodes.

These last two facts are not surprising given the volumes of residential and commercial properties in these two areas. In fact Birmingham has more households than any other Postcode Area in the UK including BT, which is the Postcode Area for Northern Ireland!

You can download a spread sheet listing the number of Postcode changes by Postcode Area by clicking here >

Postcode Changes Mapped Out

Out of curiosity, we wanted to visualize where most of the changes occurred and mapped out the number of new Postcodes and retired Postcodes by Postcode Area across the UK. This is how the changes are distributed across the UK:

Fig 1. The Volume Of New Postcodes By Postcode Area

Fig 1. The Volume Of Retired Postcodes By Postcode Area

Interestingly, there appears to be a higher volume of new Postcodes in the last 3 months in the Midlands area than the South East but a higher proportion of retired Postcodes in the North (especially Manchester).

For the next update we are also planning to look at the percentage of Postcodes created or retired in each Area.

How Does This Affect Postcode Products?

Changes to Postcodes have a direct impact on a whole range of Postcode based products which must be updated to reflect the ever-changing Postcode landscape. Here are some examples of how Postcode changes may affect you:

If you use Postcodes for Business Analysis

Look up tables which relate Postcodes to other information such as Parliamentary Constituencies, Local Authority Information, Grid References must all be updated to ensure the analysis of Postcode related records and information is accurate and up to date.

In addition to updating the Postcodes themselves, we also take the opportunity to update all the related information such as MP names, Ward names and so on to ensure these references are also current.

If you use Postcodes for Address Management

Sometimes existing Postcodes do change for households and people move in to new build homes with brand new addresses and Postcodes. Companies providing services or delivering products to these homes need to ensure their systems are up to date to capture and update these new addresses.

Our Royal Mail PAF databases are therefore all updated to reflect the latest Postcode changes and help companies keep their customer data accurate and up to date.

If you use Postcodes for mapping Sales Territories or Franchise Areas

Changes to the Postcode system can also impact the Postcode boundaries themselves which are widely used in GIS and mapping software such as MapInfo, ESRI and Intergraph products for a range of business tasks including mapping sales territories and planning franchise areas.

New Postcodes can change the Postcode structure geographically and we meticulously review these changes to ensure all our digital Postcode boundary files reflect these latest changes.

The next Postcode update is expected to take place in December 2016 but if you have any questions on the latest Postcode changes and how they may affect you please contact us.

To complement our range of Postcode Area maps, we have made available a range of Postcode and address lists in Excel format to help you with your Postcode planning.

We have three lists described below which can be used for common business tasks such as:

1. Checking and validating Postcodes
2. Cross reference Postcodes to local authorities and other geographies
3. Locating Postcodes in GIS and mapping software
4. Cleaning customer addresses to ensure accurate and successful mailings

There are three files available for immediate download:

Free Postcode Lists

Free lists of all currently valid Postcodes in the Postcode Areas of the UK. These lists are updated every 3 months and you will receive a notification to download the updated version completely free of charge!

Use For: Validating Postcodes or as a simple Postcode lookup list.

Postcode Lists With Lookup Locations

This list contains a wealth of information about the Postcodes in each Postcode Area. Not only does it contain all the Postcodes currently in use by Royal Mail but it contains every Postcode that ever existed including when the Postcode was retired.

Use For: Validating Postcodes, plotting Postcodes in mapping systems and identifying the parish, ward, local authority district that each Postcode belongs to.

The file provides the following information for each Postcode (where the information is available*):

• Postcode Sector
• Postcode District
• Postcode Area
• Built Up Area Sub Division
• Built Up Area
• Ward
• Parish
• Local Authority District
• Traditional County Name
• Region
• British National Grid Easting
• British National Grid Northing
• Latitude
• Longitude
• Date Postcode was introduced
• Date Postcode was retired/ terminated

* Fields can be blank in the data for a variety of reasons. The Postcode may be new and not have been cross-referenced to other geographies, agencies may not have supplied the information yet or the field my just not be relevant for that Postcode (not all areas are Parished for example).

This file is also updated every 3 months and updates are included in the annual subscription fee.

Postcode Lists With Addresses

A spread sheet of every residential and business postal address in the respective Postcode Area. The information is sourced directly from Royal Mail and updated every 3 months to ensure it is up to date and accurate.

Use For: Validating addresses and cleaning customer address records or as a simple address lookup list.

The spreadsheet contains the following address fields:

• UDPRN
• Organisation Name
• Department Name
• PO Box
• Building Name
• Sub-Building Name
• Building Number
• Thoroughfare
• Street
• Double Dependent Locality
• Dependent Locality
• Post Town
• Postcode
• Postcode Type
• DPS
• SU Organisation Flag

This file is also updated every 3 months and updates are included in the annual subscription fee.

To download your Postcode and address lists today, simply pick your Postcode Area from the full UK list >

Product Page: Postcode & Constituency lookup data

For a number of years, we have sourced Postcode and Parliamentary information for our customers and created authoritative lookup tables and lists that relate UK Postcode geography to the various political structures across the UK.

As a result of customer feedback and work we have done for specific clients over the past few months, we are excited to announce that the latest update provides more information than ever before and is now available in an easy to use Excel format! Continue reading to what this latest release of Postcodes & Constituencies now provides.

Every UK Postcode

The product still contains every UK Postcode that has ever existed - over 1.7 million Postcodes and over 700,000 'retired' Postcodes which are no longer in use by Royal Mail.

This means when you need to check Parliamentary information for a Postcode which is no longer in use, you can still determine the constituency it fell within and the current MP and party holding that seat.

 Westminster Constituencies

Every Postcode is linked to the current Westminster Parliamentary Constituency it falls within along with the Member of Parliament and Party that currently holds the seat. The current information is based upon the May 2015 General Election but accounts for any updates due to by-elections up to the point of the update.

Scottish Constituencies

For Postcodes in Scotland, we have always provided the name of the Scottish Constituency the Postcode falls within. In this latest release however, we have also included the name and party of the Scottish MP together with the name of the Scottish Parliament Region.

Each region is a group of constituencies, and the D'Hondt method of allocating additional member seats from party lists is used to produce a form of proportional representation for each region. Therefore, we also provide a separate sheet which provides the list of Scottish Regions and the elected Regional MSPs for each.

Welsh Assembly

For Postcodes in Wales, we have always provided the name of the Welsh Assembly the Postcode falls within. In this latest release however, we have also included the name and party of the Assembly Member together with the name of the Welsh Assembly Region. 

In addition, Assembly constituencies are grouped into electoral regions, and an additional member system is used to elect four additional Assembly Members (AMs) from each region, in addition to the AMs elected by the constituencies. Therefore, we also provide a separate sheet which provides the list of Welsh Assembly Regions and the elected AMs for each.

Northern Ireland MLAs

This sheet contains the Member of the Legislative Assembly (MLA) names and parties for Northern Ireland. The constituencies for Northern Ireland are the same as the Westminster Constituencies.

The role of the MLAs is primarily to scrutinize and make decisions on the issues dealt with by Government Departments and to consider and make legislation. There are multiple MLA’s for each constituency and the sheet Northern Ireland MLAs contains a record for each MLA with the associated Party and Constituency name.

Excel & CSV Text Formats

Old versions of Excel (versions up to and including Excel 2003) were limited to only 65,536 rows of information and therefore trying to squeeze 2.5 million Postcode rows into Excel was effectively impossible. However, Excel 2007 and later versions allow over 1 million rows per worksheet which means we can now provide the Postcode & Constituency data across 3 sheets in a single Excel workbook (Note: you must have Excel version 2007 or later to be able to open the spread sheet).

Excel makes the data easier to use and search, in particular by using the Excel Data Form tool to search for Postcode records and also reduces the amount of space required to store the data.

Both CSV and Excel options of the data are available for the same licence fee and further details can be found on the Postcode & Parliamentary Data product page.

The 2015 General Election threw up more surprises than expected with a clear majority for the Conservative party, the domination of Scotland by the Scottish National Party, the catastrophic performance by the Liberal Democrats and the impressive total vote count for UKIP which amazingly resulted in just a single Parliamentary Seat!

Following the confirmed election results we have updated our core Postcode to Parliamentary Constituency data products and look at the impact of the May General Election in the United Kingdom from a Postcode Point Of View.

Finding MPs by Postcode

With so many key seats changing hands, obviously many constituencies found themselves with new Members of Parliament for the next term. In fact, we had a change of 185 MP's across the country as a result of seats being won and lost or just a change of MP within the party. As a result, this meant that a staggering 510,591 current Postcodes across England, Scotland, Wales and Northern Ireland now have a new MP - this is almost 30% of the entire number of Postcodes in the Country.

The largest proportion of changes was obviously in Scotland where the Scottish National Party swept (almost) all before them but the actual number of Postcodes with a new MP by country is shown as follows:

England: 335,830
Northern Ireland: 15,238
Scotland: 132,161
Wales: 27,362

Postcodes By Political Party

Similarly, we can determine that 367,475 Postcodes across the UK (21%) now have a new party representing them in Westminster. Breaking this figure down to show the Postcodes gained by each political party shows the impact of the SNP on the 2105 Election.

Conservative: 102,806
Democratic Unionist: 2,064
Labour: 63,194
Labour Co-op: 57,069
Scottish National: 132,161
UKIP: 2,672
Ulster Unionist Party: 7,509

The absence of parties including the Liberal Democrats just shows that these parties did not gain any new Postcodes as a result of the election. To confirm, the above figures are the total number of Postcodes acquired - not the net gain of Postcodes.

Postcode to Parliamentary Lookup

Data such as the Postcode to Parliamentary Constituency database has become invaluable to companies analysing their own geographic and political footprint and also within the Public and Government Relations arenas. It underpins common questions such as "which constituencies are most important to our business" and "what constituency am I in by Postcode?"

Contact us for more information on Postcode analysis of the 2015 Election or details on our other Postcode based look up tables and analysis.

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