Mapping new car registrations in the UK: our approach

The Electric Car Count is a tool and data series that gives people information about the UK car market on a monthly basis. We were delighted to see it featured in the Times and the Guardian last month. If you haven’t yet explored the interactive tool, do have a look and let us know what you think.

This month, we’re delighted to add a major new feature: regional-level statistics. We’re now able to publish data showing how the mix of cars being sold is changing in different parts of the UK. In this blog we explain how we did it and how best to interpret the data. 

Obtaining car data

To produce Electric Car Count, we download data from the Driver and Vehicle Licensing Agency (DLVA)’s database of licensed vehicles. That means we get a list of all the new cars registered in any given month, with details about each vehicle, including its fuel type and registration number.

For those of a technical persuasion, we use the DVLA’s vehicle enquiry service application programme interface (API) to obtain data on new car registrations. The API allows users to access the DVLA’s vehicle licensing database, which contains information on every registered vehicle in the UK when a number plate is entered. The API returns a range of information about individual vehicles. Below is a sample of the information the API returns about an individual vehicle, and there’s a user-friendly version that you can try here.

{
  "artEndDate": "2025-02-28",
  "co2Emissions" : 135
  "colour" : "BLUE"
  "engineCapacity": 2494,
  "fuelType" : "PETROL"
  "make" : "ROVER"
  "markedForExport" : false
  "monthOfFirstRegistration" : "2004-12"
  "motStatus" : "No details held by DVLA"
  "registrationNumber" : "ABC1234"
  "revenueWeight" : 1640
  "taxDueDate" : "2007-01-01"
  "taxStatus" : "Untaxed"
  "typeApproval" : "N1"
  "wheelplan" : "NON STANDARD"
  "yearOfManufacture" : 2004
  "euroStatus": "EURO 6 AD"
  "realDrivingEmissions": "1"
  "dateOfLastV5CIssued": "2016-12-25"
}

From car information to locations

You may have noticed that in the sample response above, there was no information about the vehicle’s location. To get that information, we use the vehicle’s registration number. 

In Great Britain, the first two letters of a car’s number plate tell you where the vehicle was first registered (assuming that the number plate is not personalised and has not been transferred from another vehicle). Let’s take a random (made-up) number plate: LB19 XJR. The ‘L’ at the beginning tells us that it was registered in the London region, and the second letter, ‘B’ tells us whereabouts within that region the car was registered. Together, these two letters are known as a ‘memory tag’.

The DVLA has produced a booklet providing an overview of how memory tags correspond to different parts of the country. According to that DVLA booklet, the first letter refers to some kind of region, and the second letter indicates a particular ‘postal area’.

However, the geographical extent of these regions is not clear. For example, what are the boundaries of the ‘Garden of England’ region? And what does the unnamed ‘K’ region refer to? The areas within these regions are unclear, too. The DVLA calls them ‘postal areas’, but there is no such thing as a ‘postal area’. (See this helpful ONS overview of the official statistical geographies in use throughout the UK.)

A possible explanation is that the DVLA is referring to a ‘postcode area’. A postcode area is the area denoted by the first two letters of a postcode. For example, parts of Cambridgeshire and Essex are denoted by the ‘CB’ postcode area. However, there are 120 geographical postcode areas in Great Britain, but only 40 ‘postal areas’ listed in the DVLA’s booklet. For example, DVLA lists only three ‘postal areas’ inside the London region: Borehamwood, Sidcup and Wimbledon, whereas there are far more than three postcode areas in London: SW, N, W, E, SE, NW, etc.

We think it likely that the memory tag given to a newly registered car depended on which local DVLA office processed its registration. There were around 40 regional offices, and there are around 40 ‘postal areas’ named in the DVLA’s booklet. Although these offices closed in 2013, the location-based memory tag system remains in operation. Returning to our example of London, we can see that there were three such offices in London: one in Wimbledon, one in Sidcup and one in Borehamwood. The only remaining question is: how do you divide up the country between these now-closed offices?

Geographical proximity
To divide the country into areas that correspond to now-closed DVLA offices, we make a few key assumptions. First, we assume that DVLA offices had catchment areas, within which every newly registered vehicle received a memory tag that corresponds to the area’s DVLA office. Second,we assume that newly registered vehicles in any postcode area receive a memory tag that corresponds to the nearest DVLA office, and that the catchment areas were constructed on the basis of geographical proximity. 

Using these assumptions, we assigned each postcode area to a DVLA office, constructing a new geographical unit we refer to as a DVLA Area. We made one or two manual corrections, for example, since our methodology resulted in a few postcode areas in north Devon being assigned to DVLA Areas centred around Cardiff and Swansea. This yields the following map of DVLA Areas. 

Each of these DVLA Areas sits within what we refer to as a DVLA Region, e.g. London, Anglia, North. In our data series, we have changed some of the names of these from the original DVLA names. For example, number plates beginning with ‘G’ come from a region the DVLA refers to as ‘Garden of England’, which is not necessarily a clear name for a region, so we refer to it as ‘Kent & Sussex’. Similarly, the region corresponding to ‘K’ registrations has no name at all, so we call it Bedfordshire & Buckinghamshire. The names of the DVLA Regions and DVLA Areas that we have constructed are below, and we’ve included a rough indication of the geographical areas of the UK that they cover. 

DVLA Region (first letter of memory tag)	DVLA Area	Notes
Anglia (A)	Peterborough	This includes Peterborough and Cambridge and much of Cambridgeshire.
Anglia (A)	Norwich	This area roughly corresponds with the county of Norfolk.
Anglia (A)	Ipswich	This area roughly corresponds with the county of Suffolk.
Birmingham (B)	Birmingham	This area comprises Birmingham and a significant stretch of the West Midlands including parts of Warwickshire, Staffordshire and Leicestershire.
Wales (C)	Cardiff	This comprises much of the surrounding area of south Wales around Cardiff.
Wales (C)	Swansea	This comprises much of the area of south east Wales surrounding Swansea.
Wales (C)	Bangor	This comprises the north west corner of Wales.
Deeside & Shrewsbury (D)	Chester	This comprises most of Cheshire, but also takes in some of north Wales.
Deeside & Shrewsbury (D)	Shrewsbury	This comprises the area surrounding Shrewsbury, including much of Shropshire, parts of Staffordshire, as well as parts of central Wales.
Essex (E)	Chelmsford	This area roughly corresponds with the county of Essex.
East Midlands (F)	Lincoln	This area roughly corresponds with the county of Lincolnshire.
East Midlands (F)	Nottingham	This area roughly corresponds with the county of Nottinghamshire, including parts of Leicestershire.
Kent & Sussex (G)	Brighton	This area roughly corresponds with the county of East Sussex as well as parts of West Sussex.
Kent & Sussex (G)	Maidstone	This area roughly corresponds with the county of Kent.
Hampshire & Dorset (H)	Bournemouth	This area roughly corresponds with the county of Dorset.
Hampshire & Dorset (H)	Portsmouth	This area roughly corresponds with the county of Hampshire, including the Isle of Wight, but without northern areas of Hampshire such as Basingstoke, including parts of West Sussex
Bedfordshire & Buckinghamshire (K)	Luton*	This area roughly corresponds with the county of Bedfordshire and Hertfordshire.
Bedfordshire & Buckinghamshire (K)	Northampton	This area roughly corresponds with the county of Nottinghamshire.
London (L)	Wimbledon	This area corresponds to much of West and South West London, including parts of Surrey.
London (L)	Sidcup	This area corresponds to much of South East London.
London (L)	Borehamwood	This area corresponds to much of North and East London.
Manchester & Merseyside (M)	Manchester	This area takes in Greater Manchester and Merseyside.
North East (N)	Newcastle	This area takes in Tyne and Wear, much of Northumberland and parts of County Durham.
North East (N)	Stockton	This area includes areas of County Durham surrounding Stockton-upon-Tees and parts of North Yorkshire.
Northern Ireland**	Antrim	County Antrim.
Northern Ireland	Armagh	County Armagh.
Northern Ireland	Fermanagh	County Fermanagh.
Northern Ireland	Derry Londonderry	County Derry.
Northern Ireland	Down	County Down.
Northern Ireland	Tyrone	County Tyrone.
Oxfordshire (O)	Oxford	This area roughly corresponds with the county of Oxfordshire.
Lancashire & Cumbria (P)	Carlisle	This area roughly corresponds with Cumbria and parts of the Scottish borders.
Lancashire & Cumbria (P)	Preston	This area roughly corresponds with the county of Lancashire.
Berkshire (R)	Theale	This area roughly corresponds with the county of Berkshire, including part of north Hampshire and parts of Wiltshire.
Scotland (S)	Glasgow	This takes in much of lowland western Scotland, including Glasgow and the west half of the central belt.
Scotland (S)	Edinburgh	This takes in much of lowland south eastern Scotland and the eastern half of the central belt.
Scotland (S)	Dundee	This area takes in Dundee and its surroundings, including much of Perthshire.
Scotland (S)	Aberdeen	This area includes most of north eastern Scotland, including Orkney.
Scotland (S)	Inverness	This area takes in much of Western Scotland including the highlands and islands.
Severn Valley (V)	Worcester	This area takes in much of Gloucestershire, Herefordshire and Worcestershire, along the valley of the River Severn.
West of England (W)	Exeter	This area roughly corresponds with the county of Devon, including parts of Somerset..
West of England (W)	Bristol	This area roughly corresponds with Bristol and much of Somerset, and parts of Wiltshire.
West of England (W)	Truro	This area roughly corresponds with the county of Cornwall.
Yorkshire (Y)	Leeds	This area roughly corresponds with West Yorkshire and parts of North Yorkshire.
Yorkshire (Y)	Sheffield	This area roughly corresponds with South Yorkshire.
Yorkshire (Y)	Beverley	This area takes in East Yorkshire and much of North Yorkshire.

* We have renamed K-registered Borehamwood memory tags as ‘Luton’. The DVLA refers to Borehamwood twice in its list of ‘postal areas’, once in the unnamed K region, and once in the London region. To avoid confusion, we refer to it as Luton, where there once was a DVLA office. 

** Northern Ireland has a separate system of vehicle registration formats, which also include an indication of the place where a vehicle was first registered.

Assessing our approach: what do the data tell us?

In assessing whether we have drawn our boundaries correctly, we can look at the composition of cars in each area. While we don’t know the location of every car in the UK, we can use MOT records to help us assess whether we have drawn our boundaries well. 

The Driver and Vehicle Standards Agency (DVSA) makes the MOT database available via its own API. This database gives us a complete historic record of all MOT tests conducted in Great Britain. It tells us which cars (identified by the registration number) were tested on any day, as well as information about their mileage and whether the test resulted in a pass or a fail. As well as the publicly available data, we are grateful to DVSA for supplying us with the postcode district location of each of these tests conducted in the last few years. 

We looked at tests conducted in each postcode district of the UK, and looked at the number plates of cars undergoing their first MOT test (which is usually carried out when the car is 3 years old), to see whether the most common memory tags undergoing tests corresponds with the DVLA Area we had assigned. If we colour each postcode district according to the most common DVLA Area, we get the following result:

NB white areas are places with not MOT test centre, which therefore have no data.

This map essentially shows two things: first, the fact that we can see distinct regions among the colours means that a lot of cars don’t leave the area where they were first registered in the first three years of their life. But more importantly, it shows that we can use the memory tags to judge the location where a vehicle was registered.

Conclusion: how to use our map & regional data

The boundaries we have constructed for our DVLA Areas may not perfectly align with those showing up in this map. For any given location, for example, in Kings Lynn in west Norfolk, we cannot say definitively whether it falls into the Peterborough DVLA Area or the Norfolk DVLA area. However, that is not the point of this data series. The point of Electric Car Count’s regional data series is to provide a flavour of how fast the new car market is changing in favour of electric vehicles in different parts of the UK.

We can say that in the Peterborough DVLA area to the west of Kings Lynn, EV sales in April 2021 were well above the national average, at around 12% of all new cars, whereas Norfolk to the east, they are a much smaller part of the market at 6%. It means that Kings Lynn is at least near an area where a lot of people are buying EVs. This information can inform decisions around infrastructure: will visitors to Kings Lynn increasingly want charging infrastructure? Will the demand for vehicle-related services change as the technology nearby changes? We hope our new data series helps answer questions such as these.