[Talk-us] Address data for Miami Florida United States

Mark Wagner mark+osm at carnildo.com
Mon Sep 17 18:00:13 UTC 2018

On Mon, 17 Sep 2018 02:13:46 -0500
Aaron Forsythe <idnwys at gmail.com> wrote:

> zip codes – Zip codes are USPS routing codes.  They do not align to
> cities and may even cross over each other often.  USPS only uses the
> city field on mail as a backup to zip codes.  They fudge the cities
> intentionally to make it easier on their sorting machines.  I’d be
> cautious when getting city data from USPS based on zip codes.

"City" on a USPS address isn't the city, and never has been.  It's the
name of the sorting office.  This usually corresponds to the name of
the city (and for places with only one post office, the name of the
post office), but not always.  For unincorporated areas, it's usually
the same as the name of the nearest incorporated area, but not always:
unincorporated areas can still get post offices.

Postal Zip codes are point clouds, not areas (and Zip+4 codes even more
so).  Census zip codes are areas, but they've only got a rough
correspondence to the postal codes.


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