Today someone posted a comment to my site saying this
at [redacted] you can find a full uk postcode database with all postcodes and long / lat values. it is the only source i found where northern ireland is included. there is a download fee, future updates are free though. it contains approx 1.9 million postcodes and is complete and correct. despite the costs it seems to be recommendable for commercial projects given the completeness of the data and the update-service.
This immediately smelt a bit funny, so I headed off to their website. First I noticed the company was registered in the British Virgin Islands, which looked slightly odd. Next I checked the IP address of the commenter. Apparently he/she was located in the Philippines, which also seemed a bit strange for someone talking about UK postcodes.
So I’d be inclined to think this may not be the best company to buy UK postcode data from. But more importantly, this level of postcode data is available for nothing, with a few caveats (Northern Ireland, Channel Islands and Isle of Man are missing). Just grab it direct from the Ordnance Survey or from my website or a host of other sites packaging up the data in various ways.
Not that there is anything necessarily wrong with paying for postcode data, I provide the data for nothing and don’t promise to provide any kind of level of support, though I try to answer any questions people have. So if you want some kind of guaranteed support, paying might make sense.
One thing the free postcode data is missing is address level data. Whereas there are 1.8 million postcodes, there are 28 million addresses in the UK. To get hold of this data, you will need to pay money. And if you do want to pay for postcode data, this is almost certainly the dataset to buy, since it probably won’t cost much more than the smaller dataset and is much more versatile. And if you do decide to buy this dataset, I suggest buying it from one of the Royal Mail’s approved resellers, rather than some random dodgy site.
Update – I’ve only just been made aware of the fact that even the PAF dataset can be free if you are a small charitable organisation or a micro business. I’m not sure of the exact requirements you need to meet to get it for free, but it is certainly worth looking into.