Yes, U.S. Postal abbreviations are allowed. If the ID for a non-licensee shows “Street” and they enter “ST” on the 4473 that is OK and does not need to be corrected. Abbreviations like “APT” for Apartment and “STE” for Suite are also allowed.
You can see a list of all U.S. Postal Street Suffix Abbreviations here.
You can see a list of all U.S. Postal Secondary Unit Designators here.
