Mailbox Categories: Mailboxes are divided into two types based on installation location: indoor and outdoor mailboxes. They are categorized by assembly methods as well.

Single-unit letterboxes, apartment letterboxes, and letterbox clusters. Letterboxes are categorized by usage into residential letterboxes and smart letterboxes.

Chest. Mailboxes are categorized by installation method into: Indoor: (1) Wall-mounted (2) Inset, also known as built-in (3) Floor-standing