The Wiki says that in the UK, addr:city should be used for the “postal town”:
As such you should use addr:city to record the name of the major location (i.e. the “postal town”) as given in postal addresses even if this location is not a city
To better understand I compared the two lists. Here are some examples of widely used values for addr:city that, according to Wikipedia, aren’t post towns.
addr:city
Corresponding post town
Count
Yate
Bristol
8249
Minster-on-Sea
Sheerness
6192
Thornbury
Bristol
5339
Rosyth
Dunfermline
3885
Hadleigh
Ipswich OR Benfleet (there are two)
3880
Portlethen
Aberdeen
3788
Kirkintilloch
Glasgow
3542
Pensby
Wirral
3181
Brightlingsea
Colchester
3105
…
…
…
I suspect what’s happened is that mappers enter addresses from business cards, menus, FHRS entries, websites, or from their own experience of what people write or print on envelopes. These addresses don’t always include the post town, and addr:city tends to get used for the largest settlement in an address even if it’s not a post town. Should we document this as acceptable practice on the Wiki or is there a problem with it?
(The reason this has come up now is because I went through all addresses in Scotland that had both addr:street and addr:place. That’s clearly a mistake, no address should contain both. Sometimes the thing in addr:place was the largest settlement mentioned in the address, in that case I wasn’t always sure whether to put it into addr:suburb or addr:city. In one case I put it into suburb, because it’s not a post town, and another mapper questioned if it should not be in city instead.)
Using addr:city for post towns is an aberration and can be actively misleading. One private delivery operator’s largely deprecated database standards should not dictate how we tag things in OSM.
Welcome to the Postcode Lottery. And please note that most people do not have clue as to how to read a postcode as it is a code which many do not relate to.
Do you live at an address convenient to Royal Mail or at an address decribing your relation to local authority or geographic features?
As an example:
My Local Authority(LA) is Chorley Borough Council. I have a postcode starting PR6 which fortunately for me places me in the post town Chorley with Preston as my Postcode Area, which for me matches my LA and my perceived geographic address.Wthout a postcode I would use XX street, Chorley, Lancashire. or perhaps XX street, Chorley, near Preston, Lancashire.
However the Red Lion pub in Mawdesley, part of my LA, has a Royal Mail address of New Street, Mawdesley, Ormskirk L40 2QP. Mawdesley is addr:village and is shown in the PAF. So it is in Liverpool??? a part of Mersyside not Lancashire where Mawdesly actually is.
A large part of the problem is peoples different view of their address not aided by Royal Mail’s failure to adhere to Local Authority boundaries but creating their own concept of what an address is. This is only going to get worse when new local authorities are created which subsume the curent LA’s.
Adhering to Royal Mail’s mish mash is the way OSM has decided to go, but this is not necessarily where contributors believe they live. As OSM does not have access to the PAF I think you may have to leave these until a local knowledgable person can fix them.
The wiki seems pragmatic and I think it would be acceptable to update any addresses you know about with the postal town. Obviously for a mass update you would need a permissible data source and at least 200 or so messages on the forums on the subject (I think it needs to keep going until someone invokes the domesday book, but I’m not sure).
Lots of people have weird opinions about what their address should be - as a fun example, I remember the campaign to change the “Slough” postcode and postal town in Windsor and Maidenhead, whose residents didn’t like the “undesirable” association with the town that all their workers (including the people who sorted their mail) lived in. As a young undesirable working in Windsor myself I did take every opportunity to wind up people who cared about this.
I also remember working in customer support and having one call from a customer who insisted we change the postal town on their account to some place I hadn’t heard of - I can’t remember what happened in the end with that one (I escalated the call to a manager) but the memory did stick with me.
To be fair, the postal addresses pre-date a lot of the current local authority boundaries. In any case, I don’t think you’d want your address to keep changing every time someone tweaks the boundaries or name of your local council.
The main problem is that many people don’t appreciate that postal addresses are just that, addresses to make it convenient for the routing and delivery of mail. I’m acutely aware of this, as I grew up in Worcestershire, but had a GL (Gloucester) postcode. That was because the nearest (post) town was Tewkesbury, just across the boarder, and Tewkesbury was GL20, within the GL postcode area. Right now I live in Norfolk, but have an IP postcode, despite the Post Town actually lying in Norfolk. Apart from confusing some non-locals on occasion, it doesn’t really create any problems. And arguably in a lot of cases, the assigned Post Town actually makes more sense than naming a local authority that might be gone tomorrow.
As far as OSM is concerned, I think we have to accept Royal Mail’s near-monopoly on addresses. Most people will be used to using something approximating their official Royal Mail address, and so will be aware of the Post Town their address belongs to. It therefore makes sense that we include the Post Town in the OSM tagging. It’s also relatively straightforward to check that post towns are correct. (In most cases they can be derived from the postcode, and we have Open Data from ONS that gives the postcode for each address point.)
Thanks all. It sounds like there isn’t 100% agreement on this.
I don’t have strong views on this, I just want the Wiki page to be accurate and helpful guidance. I find that when the Wiki says “should” that sounds authoritative, it makes it sound like you can help OSM by correcting the data or by creating validation tools that flag incorrect data and it’s going to be uncontroversial.
I might edit the Wiki then to make clear that it’s not so clear cut in this case. It sounds like when you don’t know the post town, and you’re mapping an address that the local business gives as “4 Privet Drive, Little Whinging, Surrey”, there’s nothing wrong with putting Little Whinging in addr:city and moving on.
Not 100%, but I think it’s pretty well established that the UK follows the international standard here and uses addr:city for the Post Town. It’s good to have consistency like this for the benefit of data users, and it also allows us to run automated checks on addr:city values.
While there are currently lots of examples of UK data in OSM not following this, I would regard them as errors to be improved, not examples of alternative acceptable tagging. Please don’t alter the wiki to suggest otherwise, unless there’s a clear consensus in favour of doing do.
If you don’t know the post town, then just leave addr:city blank, and fill in the parts of the address you do know. From an address location, we have Open Data that will provide the UPRN (or group of possible UPRNs) and hence the Postcode. In most cases, the Post Town can then be derived from the Postcode.