LetterAgent
Mail physical letters by just asking your AI assistant.
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Yes, light colored paper is fine for most letters, as long as the ink contrasts sharply with the paper. Dark paper with light ink, or pale ink on a pale color, can confuse sorting machines and slow delivery. White or pastel paper is the safe choice for anything time-sensitive.
Sorting machines read addresses with cameras, not eyes. They look for dark marks on a light background, and they work best when the contrast is strong. A cream or pale blue sheet with black ink reads almost as well as white paper. A deep red or navy sheet with black ink does not, because the camera struggles to tell the ink apart from the paper. When the machine cannot read the address, a person has to read it instead, and that hand step is what slows the letter down.
The envelope matters even more than the letter inside it, since the envelope is what the machine actually sees. A colored letter in a white envelope travels like any ordinary letter. A colored envelope with a dark or patterned surface is the one that risks a misread. If you love colored paper, pair it with a plain light envelope and you keep most of the charm with none of the risk.
| Paper choice | How it travels |
|---|---|
| White or ivory | Best machine readability, no issues |
| Pastel pink, blue, yellow, green | Reads well with black or dark blue ink |
| Bright neon or fluorescent | Can glare under scanner lights; avoid for formal mail |
| Dark navy, black, deep red | Poor contrast with most inks; likely hand sorting |
| Patterned or heavily textured | Pattern can break up printed text; keep print on plain areas |
Black ink is the safest choice on any light color, and dark blue is a close second. Gel pens and fountain pens both work, but test one line first: some inks feather or bleed on cheap colored stock, and a fuzzy line is harder for a scanner to read than a crisp one. Avoid metallic inks, glitter inks, and light colors like silver or pale gold for the address itself. They may look lovely in person and vanish under a scanner's light.
If you are printing rather than handwriting, the same rule holds. A laser or inkjet printer lays down dark toner or ink that reads well on pastel stock. Just check that your printer's paper setting matches the stock weight, or the toner may flake off textured colored paper. A quick test page, read at arm's length in daylight, tells you most of what you need to know.
Color alone does not change postage. Postage follows size, weight, thickness, and shape, not the color of the paper. A standard letter on pastel paper costs the same to mail as the same letter on white paper, as long as the envelope stays within the standard size and weight limits. What can change the price is everything that often travels with colored paper: heavier card stock, added decorations, or an odd-sized envelope.
In Canada, the same principle applies: Canada Post prices by format and weight, and a colored letter in a standard envelope is a standard letter. The one exception to watch for is envelopes with dark borders or patterns near the address area, which can interfere with the fluorescent marks sorting equipment uses. Keep the address area plain and light, even on a colored envelope, and you avoid that trap.
Skip it for anything where a misread address would be costly: legal notices, tax mail, job applications, and letters with a hard deadline. For those, white paper and a plain envelope are not boring, they are insurance. A hiring manager or a court clerk will not remember your paper color, but they will notice a late arrival.
Colored paper shines for personal letters, thank-you notes, invitations, and holiday mail, where the paper itself is part of the message. A pale pink letter to a friend, or a soft blue note to a grandparent, reads as warm before a single word is read. That is exactly the kind of mail where a small delay would not matter, and where the color earns its keep.
LetterAgent prints letters on standard letter-size paper, single-sided, in black-and-white or colour, and mails them in a double-window business envelope. You describe the letter to your AI assistant, approve the exact quoted price, and it is printed and mailed. The print stock is standard, so if your letter's charm depends on a specific colored paper, mail that one yourself and use LetterAgent for the letters where standard paper is fine. Recipients in the US and Canada are covered, and senders can be anywhere in the world.
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