I know this has come up before: searching in openstreetmap on just a postcode lands a point a significant distance from the actual addresses that have that postcode.
“LE19 4ET” takes you to:
which is a pin near Glenmore Road when it should be Ardle Drive in Lubbesthorpe, Leicester.
I have added to the Ardle Drive ‘residential road’ feature both addr:postcode and postal_code tags, but neither seem to work (even after waiting a couple of days for search databases to catch up etc.). This is the link to the road:
I know that ‘nomanitim’ is the search engine and generates a pin-point based on an aggregate of the data that it can find locating the postcode … but it doesn’t seem to be picking up the tags on the road and instead getting a bogus location (or guess) from somewhere else.
The OS map is correct:
E.g. no. 1 Ardle UPRN: 10001239522
Back in OpenStreetMap, if I search on ‘LE19 4ET Ardle’ it will give a correct result. The problem is delivery drivers just enter the postcode without any other data … and so get directed over to Glenmore!
I don’t know if Nomanitim uses postcodes from roads, @lonvia do you know?
Anyway addr:postcode on a road seems weird, real address points are probably better. (addr:housenumber= + addr:street=Ardle Drive + addr:postcode=LE19 4ET)
Nominatim takes addr:postcode and postal_code from streets into account, so your edits should have worked.
Turns out there is a little bug in the software where it wouldn’t take updates into account when the postcode moves in a north-eastern direction. Slightly embarrassing beginner’s mistake, really. Give it a couple of days and we should get this fixed.
In the meantime, while postcode on the streets are okay, if you have a bit of time on your hand to add the houses in the street and add the full addresses to them, you’d make OpenStreetMap that little bit better. Otherwise, just postal_code on the street will be enough, no need for two tags with the same meaning.
FYI: the postcode LE19 4ET is relatively new, and in the latest Code-Point Open dataset provided by Ordnance survey, it has a low “quality score” and only an approximate position - which is the location you’re seeing in the search on OSM.
Without OpenStreetMap data to help Nomanitim (or any other search function), it looks to be falling back on the incorrect location from Code-Point Open.
(Code-Point Open seems to be quite slow at getting accurate locations for some new postcodes. Does anyone know if the most recent ONS UPRN datasets have that postcode tied to any UPRNs yet?)
As you might have guessed, its a new build street … I will keep the street postal_code tag for now, but in time will add houses as they are constructed and occupied.
The outward part of a postcode tagged as postal_code on a street can be quite useful, particularly when a street name occurs more than once in a local authority area. In many cities it’s on the street name sign and verifiable on the ground.
I’m a bit more dubious about a full postcode, even when there’s a single postcode for all the houses on a cul-de-sac.
The ONS issues NSUL and the UPRN Directory, both of which allow you to associate postcodes with individual property numbers (UPRNs) and hence with geographical locations. There is an NSUL postcode overlay which can be used in JOSM and iD. The details are here [Talk-GB] NSUL postcode layer Inbox - Now back online . You can add the overlay manually to both editors. The overlay has not been updated.
If you want something more recent, you could look at https://blue.subbasis.net/postcodes/postcodes-2025-03.gpkg.xz which was created by @JB_Robertson. It needs QGIS (FOSS) to open it, which is not so convenient. It is also a bit cumbersome because QGIS is a large download and the file itself is large. It works differently because JB_Robertson has drawn areas around each postcode. You click in the area to see what the postcode is. Occasionally areas overlap and you need to click in several places to see what the postcodes are.