LetterAgent

Mail physical letters by just asking your AI assistant.

Status: LetterAgent is currently in private testing ahead of public launch. Everything on this page describes the service as it works today.

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Can the post office open my mail?

Usually no. Sealed First-Class and Priority Mail in the US is protected against inspection: opening it requires a search warrant. But there are real exceptions. Customs can open international mail, undeliverable mail can be opened to find the sender, and discounted classes like Media Mail can be inspected to check the contents qualify.

When is your mail protected?

In the United States, sealed First-Class Mail, Priority Mail, and Priority Mail Express are "sealed against inspection." That phrase is doing real legal work: it means postal employees cannot open the piece, and postal inspectors need a federal search warrant to open it, just like police need a warrant to search your home. The Fourth Amendment protection follows the letter from the mailbox to the doorstep. A postal worker who opens your sealed letter out of curiosity is committing a federal offence, not bending a workplace rule.

When can it be opened without a warrant?

Customs. Mail crossing a border is different. US Customs and Border Protection can open international mail and parcels to enforce customs and contraband laws, no warrant needed. In Canada, the CBSA has equivalent authority over incoming international mail.
Undeliverable mail. When a piece cannot be delivered and cannot be returned, it goes to the Mail Recovery Center in Atlanta, where staff may open it to find a sender address or identify the owner. This is the "dead letter office" doing exactly what its name suggests.
Suspected danger. A leaking, ticking, or otherwise suspicious package can be isolated, X-rayed, and handled by inspectors. Opening still generally needs a warrant, but nobody is delivering a suspected bomb while the paperwork clears.
Discounted mail classes. This is the one that catches senders. Media Mail, Bound Printed Matter, and similar discounted classes are not sealed against inspection. USPS can open them at any point to verify the contents actually qualify for the cheap rate. Mail a video game as Media Mail and you have given USPS written permission to look inside, plus postage due when they catch it.

What about packages versus letters?

The protection follows the seal, not the shape. A sealed Priority Mail box gets the same warrant protection as a sealed letter. An unsealed parcel, or one sent at a class that is not sealed against inspection, does not. This is why the Media Mail exception matters more than people think: the discount you get for mailing books comes with a standing invitation for USPS to verify you are mailing books. If privacy matters for the contents, send it First-Class or Priority and keep it sealed.

Mail type	Can USPS open it without a warrant?
Sealed First-Class letter	No, warrant required
Priority Mail / Priority Mail Express	No, warrant required
Media Mail, Bound Printed Matter	Yes, to verify contents qualify for the rate
International mail (customs)	Yes, by CBP/CBSA at the border
Undeliverable mail at the recovery center	Yes, to find the sender or owner

Does this work the same in Canada?

The shape of the protection is similar, the statutes are different. Opening someone else's mail is an offence under the Canada Post Corporation Act, and sealed domestic letter mail is protected in practice the same way. Canada Post's undeliverable mail office can open items to try to find a return address, and international mail is subject to CBSA examination at the border. The practical rule is the same on both sides of the border: sealed domestic mail is private, and the exceptions are about borders, dead letters, and discounted rates, not routine snooping.

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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.

Need help? Ask your assistant: it can check a job's status any time. If it ever can't handle something: hello@getletteragent.com