GLOSSARY
Address standardization
By Justin Winter · Updated August 28, 2026
Rewriting an address into the exact form USPS uses — canonical abbreviations, directionals, unit designators, and ZIP+4.
Standardization takes "123 north main street, apartment 4" and returns "123 N MAIN ST APT 4" with the correct ZIP+4. It is a lookup against USPS data, not a formatting preference.
Everything downstream depends on it: barcoding, automation rates, deliverability checks, and duplicate detection on a mailing list all assume a standardized address.
See also
- CASS certification — A USPS certification programme for address-matching software, confirming it can correctly standardise and code addresses.
- Delivery Point Validation — A USPS check that confirms an address is a real, individually deliverable delivery point — down to the apartment or suite.
- Intelligent Mail barcode — The USPS barcode printed on letter mail that encodes routing and a unique piece identifier, enabling automation rates and tracking.
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