Curbside Mailboxes
Mailbox Size & Construction Standards
A mailbox with the Postmaster General's (PMG) seal of approval meets USPS size and construction standards. If you build your own mailbox or buy a custom-made one, it must meet the PMG standards. Show your local postmaster your mailbox plans or your custom-made box for approval.
Want to buy a mailbox big enough for packages? See Fortknox Mailboxes.