Street naming and numbering

Page updated on: 31/08/2023

We are responsible for the naming of all roads and streets, and for the naming and numbering of all properties (residential, commercial and industrial) within the County of Carmarthenshire

Royal Mail has no statutory power to name a street, name or number a property, or rename or renumber a property.

An address can only be created and given a postcode by Royal Mail once it has been officially named and numbered by us. So if you are planning a new development, constructing a new property, converting an existing property, or wish to change the name of a property you must contact us with the address creation or amendments required.

Failure to register your property will mean that any address created will not be an official address and this will lead to problems. For example, the address will not be recognised by the Royal Mail, the Land Registry, delivery companies, or utility services; and difficulties may arise in relation to your registration for voting and the supply of credit cards. Moreover, ambulance, fire and police services may experience difficulty in locating the address in the event of an emergency.

It should also be noted that we have the power to enforce changes to unofficial addresses in order to ensure compliance with standard conventions and that council policy for street naming and numbering is maintained. It is in your best interests to advise us of new naming and numbering requirements at the earliest opportunity.

The Street Naming and Numbering service is required if:

  • You have built a new property
  • You have converted a property like a barn into a dwelling, or a single property into flats.
  • You wish to rename your property
  • You wish to add a name to an existing numbered property
  • You have built a new development of more than one dwelling. This may include naming any roads within the development
  • You wish to amend layout of new developments that have already gone through the naming & numbering process.
  • Residents wish to rename and existing street
  • You require confirmation of an address

It is strongly advised that any Street Naming and Numbering applications made for new properties are submitted as early as possible in the development process. This will prevent any delay in obtaining services for the properties.

Payment must be submitted with your application otherwise it will not be validated and no work will be undertaken on processing or assessing your application. You will need to provide the following details:

  • Type of application e.g. street naming & numbering application.
  • Application reference number, or name and application location if you do not have a reference number yet.
  • The correct application fee as stated in the scale of charges

By Telephone

We accept card payment. If you’d like to speak to a member of staff in the cashier's team - call 01267 228686 between 9 - 5.

By Post

Please make cheques payable to ‘Carmarthenshire County Council’ and post to: Planning Services, Civic Offices, Crescent Road, Llandeilo, SA19 6HW.

In Person

Payments can be made in person by cash, credit/debit card or by cheque. Details and opening times can be viewed for each location:

BACS Payment

Please email for further details.

When a new development has been approved, addresses are created by the Council as ‘provisional’ entities. The details of the proposed development are shared with Royal Mail who subsequently ‘hold and record’ the addresses on their ‘Not Yet Built’ address database. To avoid any issues of post being sent to non-existent properties the addresses are not activated until occupation or the properties are near completion and therefore are able to receive postal services.

As each property nears completion the developer will be required to notify the Street Naming and Numbering team and request that the address be activated for use. Upon notification confirmation will be issued to all internal services and external partners, including the emergency services.

Royal Mail will be notified to ensure that the appropriate records are moved from their ‘Not Yet Built’ database into the Postcode Address File (PAF) making it available for general use and referencing across the United Kingdom within 24-48 hours, although this addition/correction can take several months to filter through to end users of Postcode Address File data.

This will happen as external companies update their own databases with the latest Address Management Products over which Royal Mail have no jurisdiction.

  • British Gas
  • BT    
  • Community/Town Council    
  • Council Tax    
  • Dyfed Powys Police Headquarters    
  • Electoral Registration   
  • Land Registry    
  • Mid and West Wales Fire Authority   
  • Ordnance Survey   
  • Royal Mail    
  • Welsh Ambulance Service
  • NHS Trust (Central and West Region)    
  • Welsh Water    
  • Western Power Distribution