How to Write a Purchase Order

A purchase order (PO) is the document a buyer sends to a vendor to order goods. It lists items, quantities, and prices, plus a unique PO number used to track the order from request to invoice. It is not the same as an invoice, and it is usually simpler than a full sales agreement.

Fill in our free purchase order template using the fields below.

Purchase order vs invoice

The buyer creates the PO before the purchase to request goods. The seller creates an invoice after supplying them to request payment. The PO number should appear on the invoice so both sides can match the bill to the original order.

1. Buyer, vendor, PO number, and date

Identify both companies (or people), give the PO a unique number, and date it. The number is what accounting uses later — do not reuse it.

2. Shipping details

Ship-to address, requested delivery date, and shipping method. Missing these is how orders arrive at the wrong warehouse.

3. Itemize every line

For each item: description, quantity, unit price, and line total. Add SKU or part numbers if you have them. The more precise the line, the fewer substitutions you get.

4. Subtotal, tax, shipping, and total

Show the math. If tax or shipping is estimated, say so. The vendor should not have to guess the authorized amount.

5. Special instructions and authorization

Add packing notes, a required reference, or "do not substitute." Then have an authorized person sign or approve the PO. You can sign it electronically and send it to the vendor so both sides keep the same copy. If the deal needs warranties, inspection rights, or a payment schedule, wrap it in a sales agreement rather than relying on the PO alone.

Disclaimer: This article is for general informational purposes only and is not legal or accounting advice. Whether a PO becomes a binding contract can depend on how the vendor accepts it.