LetterAgent
Mail physical letters by just asking your AI assistant.
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In the United States, no. Only mail that USPS itself delivers may be placed in a mailbox. Dropping your own flyer, menu, or note into someone's mailbox violates the federal mailbox monopoly and can carry federal penalties. This is general information, not legal advice. Use the door slot, hand it over in person, or mail it properly.
The rule dates to 1934. Congress gave USPS exclusive access to mailboxes so that the postal service could guarantee private, secure delivery and protect its revenue. The effect is simple: if it did not arrive with postage paid and through USPS, it does not belong in the box. That covers flyers, business cards, and newspapers tucked inside the mailbox, even one wedged under the flag or in the door of the box. A receptacle designated for mail is USPS territory the moment it is installed.
Violating the mailbox restriction is a federal offense that can bring fines, and postal inspectors do enforce it against businesses that blanket neighbourhoods with unmailed flyers. Enforcement usually starts with a warning, but the fines are real enough that legitimate distributors do not risk it. The law also protects you as a recipient: nobody but the carrier and your household should be reaching into your box.
| Placement | US rule | Notes |
|---|---|---|
| Inside the mailbox | Only USPS-delivered mail | Your own flyer here breaks federal law |
| Newspaper box or tube beside the mailbox | Generally allowed | Separate receptacles are not mailboxes |
| Door slot or between screen door and door | Allowed | You are on the homeowner's property, not in the mailbox |
| Handed to the person | Allowed | The simplest legal option |
| Mailed with postage | Allowed | Becomes USPS-delivered mail |
Canada does not have the same strict mailbox monopoly. Canada Post boxes and community mailboxes are still Canada Post property, and you should not stuff flyers into other people's locked compartments, but the famous American prohibition with federal penalties is a US feature. That said, many Canadian municipalities have their own flyer-distribution bylaws, and most households have strong feelings about unsolicited paper. The courteous routes still win: door slots, hand delivery, or proper postage.
If you are distributing flyers, slide them through the door mail slot or leave them folded in the door handle. If you are reaching one specific person, hand it to them or mail it: a stamped letter lands in the mailbox legally and carries more weight than a loose flyer anyway. For bulk outreach, addressed mail through a service like LetterAgent is the compliant path. You describe the letter to your AI assistant, approve the exact quoted price, and each piece arrives as real mail, legally in the box.
Ready to mail it? Send your letter with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and it is printed and mailed.
LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
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