LetterAgent
Mail physical letters by just asking your AI assistant.
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Mail a large envelope like a 9x12 as a USPS "flat": address it clearly, seal it well, and pay the flat rate, which costs more than a letter stamp because oversized pieces sort differently. Anything rigid, lumpy, or unbendable usually needs extra postage too. For paper stacks or photos, a rigid mailer marked "Do Not Bend" keeps contents safe.
| Letter | Large envelope (flat) | |
|---|---|---|
| Size | Up to 6-1/8 x 11-1/2 inches | Up to 12 x 15 inches |
| Thickness | Up to 1/4 inch, must bend | Up to 3/4 inch |
| Postage | One stamp per ounce | Higher flat rate, priced by weight |
| Typical use | Letters, bills, folded documents | Unfolded documents, photos, certificates, magazines |
Less than people think. "Do Not Bend" is a request written on the envelope, not a postal service you paid for, so it does not guarantee hand processing. What actually protects your contents is the mailer itself: a rigid cardboard mailer resists bending on its own, with or without the handwriting. If the contents truly cannot bend, say so by choosing rigid packaging rather than relying on two words in marker. And remember that rigid contents can push a letter-size piece into nonmachinable territory, which means extra postage either way.
Seal it like it will be dropped, because it will be. Large envelopes burst open in sorting equipment more often than letters do, so use the peel-and-seal strip plus a strip of packing tape across the flap for anything valuable. Keep the address in the center of the envelope, clear of the edges, since the outer inch is where handling marks and barcodes land. For photos or certificates, sandwich them between two pieces of stiff cardboard inside the mailer; the cardboard takes the bend so the print does not.
Past 3/4 of an inch thick, or past 12x15 inches, your envelope stops being a flat and becomes a parcel, with parcel pricing. That is the point where a padded mailer or a small box usually makes more sense: they survive the parcel stream better than an overstuffed envelope, and the price difference is small. A 9x12 stuffed until it bulges is the worst of both worlds: parcel-priced and fragile.
Canada Post has its own oversize categories with the same idea: standard letter mail is the cheapest, and anything bigger, thicker, or rigid steps up in price. Rigid photo mailers and cardboard document mailers are sold at most post offices and work the same way on both sides of the border.
Ready to mail it? Send your letter with LetterAgent - describe it to your AI assistant, approve the exact quoted price, and it's 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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