What's not allowed

• Personal information
• Bills and statements
• Handwritten or typewritten matter
• First-Class enclosures
• Forwarding or return
• Extra services
• Endorsements
• Names on the address line

Content

• Personal information (143.3.2). Nothing about an individual.
• Bills or statements of account (143.3.3). These must go First-Class.
• Handwritten or typewritten matter (143.3.4).
• Anything required to go First-Class, or authorized as a Periodical (143.3.1).

Enclosures and attachments

• No First-Class enclosures or attachments (143.3.5).
• Labels, stickers, release cards and repositionable notes are allowed under their own rules.
• Other attachments are allowed only if the host piece is at least 0.009 inch thick, the attachment is secure and no larger than the host, and every piece carries an identical one in the same position.

Services

• No forwarding or returns (143.2.3).
• No extra services (143.2.4): no tracking, certified mail or insurance.
• No ancillary service endorsements (143.1.2): no "Return Service Requested" or similar.

Address

• No names. Pieces carry a simplified address ("Postal Customer" or "Residential Customer") under 602.3.