We have a database of postal_codes from which we update the state & lat/long of contact's addresses - however, it dates back 20 years and there are a bunch of postal_codes not in it - meaning we don't add state/lat/long data to all the addresses we could. If we can figure out how to get an updated version it would be good. (alternatively we can also do ad hoc updates for specific postal codes - eg. get the lat-long & state from google)
https://raw.githubusercontent.com/eileenmcnaughton/org.wikimedia.geocoder/refs/heads/master/sql/install_zip_data_set.sql