Yes, it is illegal to hang marketing materials on mailboxes. This is because every component of a mailbox is considered the exclusive domain of the. Putting a flyer in someone's mailbox is actually illegal under federal law, but there are plenty of legal ways to get your message out. Mailboxes are reserved exclusively for items carrying U. mail system, and this includes placing items in a mailbox that are not properly addressed or if you are not a postal worker. The United States Postal Service (USPS) maintains strict guidelines about mailbox decorations. This regulation is established under Title 18, Section 1725 of the United States Code, which prohibits the placement of mailable and non-mailable.
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