Categories of International Mail

  1. LC Mail (Letters and Cards)
    • "LC" is an abbreviation of the French term "lettres et cartes", which means "letters and cards." This category encompasses letters, letter packages, postcards, postal cards, and aerogrammes. All "LC" mail receives First Class Mail service in the United States, is dispatched by the fastest transportation available, and travels by airmail or priority service in the destination country. All "LC" mail should be marked "AIRMAIL" or "PAR AVION."
       
  2. AO Mail (Other Articles)
    • "AO" is an abbreviation of the French term "autres objets", which means "other articles." This category encompasses the various classes of printed matter (i.e., regular printed matter, books and sheet music, and publishers’ periodicals), matter for the blind, and small packets.
       
  3. CP Mail (Parcel Post)
    • "CP" is an abbreviation of the French term "colis postaux", which means "parcel post." This category is similar to domestic parcel post.