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.

Home > Guides > POs to US suppliers

How do I mail purchase orders to US suppliers?

Mail the purchase order like you'd email it: a printed PO with your PO number, line items, payment terms, and bill-to/ship-to details, addressed to the supplier's accounts-payable department. Mailed POs win when email filters eat PDFs, when their AP team works from physical mail, or when you need a paper trail an inbox can't lose.

What does an AP department expect to see on a mailed PO?

US supplier accounts-payable teams process thousands of documents a day, and they sort by a few key fields before reading anything else. Put these on page one, high up, and don't bury them in body text:

Field	Why it matters
PO number	The single most important field. AP clerks match invoices to POs by this number alone: a PO without a visible PO number will be set aside or returned.
Ship-to vs. bill-to	Show both addresses. Many businesses bill to a head office but ship to a warehouse; mixing them up delays fulfillment.
Payment terms	State the terms you negotiated (e.g. Net 30, 2/10 Net 30). Terms on the PO become part of the agreement: don't leave them verbal.
Remit-to details	Only needed on POs if you also send remittance advice with payment: your company name, what you're paying, and which invoice or PO numbers the payment covers. Remittance info is what lets their cash-application team match your check or wire to the right invoices.
Authorized signature / name	Many suppliers require a named authorizer for the PO to count as a binding commitment, especially for first orders over a few thousand dollars.

One non-obvious point: if the supplier gave you a vendor number or customer number during onboarding, print it right under your PO number. AP software often files by vendor number first, PO number second: having both gets your document into the right queue immediately.

When does a mailed PO beat an emailed PDF?

Most of the time email is fine, but the exceptions are specific and recurring:

Attachment-stripping firewalls. Some suppliers' mail servers silently quarantine PDFs from unknown senders. A paper PO bypasses this entirely, and the double-window envelope shows the supplier's name through the window, so it lands in the right department's mail tray.
Old-school AP departments. Plenty of mid-size US distributors still run a "physical mail first" workflow: incoming paper goes to a scanner queue that is the official record, and emailed PDFs have to be printed by someone to get into the same queue.
Credit applications and W-9s. A request for a supplier's W-9 (which you need before you can pay them) is itself often mailed, because vendors treat it as semi-formal. Include a self-addressed note telling them exactly where to send it back: many will just fax or email it, but asking in writing sets a paper trail if you later need to show you requested it.
Disputes. If a supplier claims they never received your order, a mailed PO with a clear send record is harder to argue with than an email nobody opened.

Should I send a PO by certified mail?

Usually not. Certified mail adds tracking and proof of delivery, but it also slows the document down: someone has to sign for it, which can stall a PO in a mailroom for days. Reserve certified mail for POs tied to contract deadlines or dispute situations where you need proof the supplier received it. Ordinary first-class mail is the default for routine purchase orders.

How do I mail a PO with LetterAgent?

Draft the PO as you'd normally prepare it: company letterhead, PO number at top, line items, terms, bill-to/ship-to, and your signature block. Then describe it to your AI assistant (or use the API), approve the exact quoted price, and the letter is printed and mailed to the supplier's US address. Since LetterAgent's envelope is double-windowed, make sure the supplier's name and department appear in the first few lines of the letter itself so it shows through the address window.

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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'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.

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