Local Keys

If you are submitting electronic documentation (eDoc) to PostalOne!®, one of the critical pieces of information required to identify postal facilities are the locale keys. Locale keys are unique identification codes that are assigned by the USPS® to each postal processing and delivery facility. This allows for very precise identification of the postal facilities that mailers are using for their origin entry and for any additional entry points at which mail is entered. There are a number of fields in the Mail.dat® file where these locale keys may be populated for communication of this information to the USPS and other entities in the mailing process.
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