Open Access UK Unit Postcodes

The Ordnance Survey released their Code-Point Open product a few years ago that has the OSGB centroids of the unit postcodes. It’s very useful but is only points - if you want the postcodes areas as polygons then you need to license Code-Point with Polygons (snappily titled!). A number of people have derived unit postcode areas using Voronoi polygons including more recently Mike Spencer with some intro at his Scottish Snow site. It’s worth noting that Voronoi diagrams equally partition space between points and nothing more - they are not equivalent to unit postcodes (which can be arbitrary) but are a reasonable first guess. One dataset worth having for your arsenal of spatial data!