Postcode Address File

The Postcode Address File (PAF) is a database which contains all known "Delivery Points" and postcodes in the United Kingdom. The PAF is a collection of over 29 million Royal Mail postal addresses and 1.8 million postcodes. It is available in a variety of formats including download, compact disc and previously available as Digital Audio Tape. As owner of the PAF, Royal Mail is required by section 116 of the Postal Services Act 2000 to maintain the data and make it available on reasonable terms. A charge is made for lookup services or wholesale supply of PAF data. Charges are regulated by Ofcom. It includes Small User Residential, Small User Organisation and Large User Organisation details. There have been requests as part of the Open Data campaign for the PAF to be released by the government free of charge.

The "delivery points" held on the PAF are routing instructions used by Royal Mail staff to sort and deliver mail quickly and accurately. Elements of the address, including the post town and postcode are occasionally subject to change, reflecting the operational structure of the postal delivery system. Each address is therefore not necessarily a geographically accurate description of where a property is located. Buildings which contain internal flats or businesses but only have one external front door, will only have those internal elements recorded in PAF if the Royal Mail have direct access to them using a key or fob.

Some versions of the PAF also contain the 'Delivery Point Suffix (DPS)' used in CBC (Customer Bar Code). Alternatively the DPS can be found using Royal Mail's 'Postcode Information File (PIF)' .

The PAF licence sets out what PAF can be used for. Licensing options include internal and external use and also more advanced options such as bureau services and broker groups.

An example of typical internal use is an employee of a licensed call centre who uses a PAF-based solution to look up and verify customer addresses. The PAF data is only being used within the licensed end-user and is not passed on to any other legal entity.

On the other hand, an example of external use would be a company which provides a PAF-based address look-up on their customer facing website for their own customers to use when they order goods or services.

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