post code truncated for street address

[msuk1]

Hi team,

when I use the suggest api, the post code is often truncated for the street address vs a point address, eg:

point address:
query: 10 downing street
responses:
- 10 Downing Street, Saint. James's, Westminster, London, England, SW1A 2AU, GBR
- 10 Downing Street, Saint. James's, Westminster, London, England, SW1A 2AB, GBR

street address:
query: downing street
responses:
- Downing Street, Saint. James's, Westminster, London, England, SW1A 2AA, GBR
- Downing Street, Saint. James's, Westminster, London, England, SW1A 2, GBR

There are 4 post codes, but only 3 are valid, I'm not sure why 'SW1A 2' is returned.
How can I fix this? The truncation occurs in many cases when I've tried searching for a street name.

Also it seems that the correct post code for 10 downing street is SW1A 2AA, but I guess that's a data quality issue which will hopefully eventually be solved.

Thanks.

[BradNiemand · Accepted solution]

Street addresses in Great Britain can have multiple postal codes associated with them, and the first two to four characters of the postcode represent the outcode (or outward code) of a post code. The outcode contains the postcode area and the postcode district. The remaining characters in a postcode represent the incode (or inward code) of a post code.

When the input is a street name, Esri provides a truncated candidate with the characters common to all post codes on that street segment. Esri does this when there are multiple postal codes associated with a street segment. The truncated entry applies to all potential post codes used by that street segment.

We appreciate the feedback on the post code for the prime minister’s residence.

Brad

[msuk1]

Thanks for sharing Brad. It will be useful for that to be documented here:
https://developers.arcgis.com/rest/geocode/api-reference/geocoding-find-address-candidates.htm
Though the above query was for the suggest API.
Will note, that the suggest API can return the common postcode (SW1A 2) and a specific postcode (SW1A 2AA) in the results of the same query.
Yes correct, I used the prime minister's residence as an example 🙂