LetterAgent
Mail physical letters by just asking your AI assistant.
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Mail a client letter on business letterhead or plain professional paper, with the client's name, your reference or account details, and one clear purpose in the first paragraph. Follow-ups, thanks, and account letters all work the same way: short, specific, and filed easily.
Five pieces, in order: your business name and return address, the date, the client's full name and mailing address, a subject or reference line, and the body. The subject line is the piece most small businesses skip, and it is the piece that helps most: a client or their assistant can file the letter without reading it twice. Include an account number, project name, or invoice reference in that line when one exists, but never include a full bank account number, password, or other sensitive credential in a letter; use a reference the client can match to their own records. Sign with your full name and role, and add a phone number and email address so the client can reply by the faster channel even though you wrote by paper.
| Letter type | Purpose in one line | Key line to include |
|---|---|---|
| Follow-up | Confirm what was agreed and what happens next | The date of the meeting or call |
| Thank-you | Thank them for business or a referral | The specific project or order, named |
| Account update | Tell them about a change to their account | The effective date of the change |
| Welcome | Confirm the new relationship and next steps | Who to contact with questions |
| Closing | Wrap up a project cleanly | Where records will be kept |
A follow-up letter should read like minutes, not marketing. State what was discussed, what was decided, who owns each next step, and by when. That record protects both sides: if memories differ later, the letter settles it without an argument. Keep the tone neutral and factual, even if the meeting was tense. Send it within a few business days of the meeting, while details are fresh for both of you. If the letter carries a deadline or a formal notice, consider tracked delivery: US Certified Mail or Canada Registered Mail gives you proof of mailing and delivery, which matters if the client later claims they never received it. For routine follow-ups, standard mail is fine.
A client thank-you letter should be short and specific: thank them for the named project, order, or referral, say what you valued about working with them, and close without pitching the next sale. A thank-you that turns into a sales letter feels like a trick, and clients notice. An account letter is different: it must be precise above all. State the change, the effective date, and what the client needs to do, if anything. If nothing is needed from them, say so plainly: "No action is needed" saves a phone call. Watch privacy here too. Account letters often travel to a home address, so keep sensitive details minimal and direct the client to a secure channel for anything that should not sit on paper.
Address the letter to a named person, not just a company, whenever you can: "Ms. Priya Raman, Acme Accounting" reaches a desk, while a company-only address can sit in a mailroom. Use the client's preferred form of address if you know it, and double-check spelling of names and street addresses before posting, since a returned business letter wastes days. In the US, a standard business letter fits a normal envelope at standard postage; in Canada, domestic business mail follows the same pattern, with a higher rate for cross-border letters. LetterAgent prints letters on 8.5x11 paper in a double-window envelope and mails to US and Canadian addresses from a chat with your AI assistant, with the price quoted up front and approved by you first, which suits one-off client letters when you have no office printer handy.
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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