The Postcode Address File is a datafile of UK Postcodes and the appropriate street addresses, kept up to date and owned by Royal Mail, then licenced out for an annual charge.
This project was started to try and build a freely available database containing mappings of street addresses to postcodes, a database which can be used by anyone for any purpose.
There are over one point six million postcodes in the UK alone, so this is quite an ambitious goal and we need the support of people like yourself, people who are interested in using the data or API, who add postcodes and street addresses to the database. We dont want house numbers, and dont collect any data that could be used to identify you from the postcode so please, if you are interested in using this data for free without restrictions, submit your postcode to the database or review postcodes we have to help us build a complete, accurate, index of the UK.
To get started, use the 'Search for a postcode' link on the menu. If we don't have the postcode you're searching for, you'll be asked to add it. If we have it, you'll see what we have for that postcode. If its wrong, you can add a correction, and down-vote the incorrect one. By doing it this way, we can able to moderate the postcodes coming in and hopefully ensure that the data we have is accurate.
If you add a postcode while logged in, your name or nickname will be attached to the postcode so you can be given credit for helping to build the data set.