What Is a Purchase Order (and How to Raise One)

A plain guide to purchase orders: what a PO is, how it differs from an invoice, what to put on one, and how PO numbers work. Free purchase order generator.

Updated 4 min read By CodingEagles
Free tool Purchase Order Generator Raise a purchase order and download the PDF. Open tool

A purchase order, or PO, is a document a buyer sends to a supplier to formally request goods or services at an agreed price. It lists the items, quantities and prices and carries a unique PO number. Once the supplier accepts it, it becomes a binding agreement. The purchase order generator lays this out and gives you a clean PDF to send.

Here is how a PO works and what belongs on one.

What a purchase order is for

A PO puts an order in writing before anything changes hands. It does three useful things:

  • Confirms the order. Both sides have a record of exactly what was ordered, in what quantity, at what price.
  • Controls spending. Inside a business, raising and approving a PO is a way to sign off a purchase before money is committed.
  • Simplifies checking. When the supplier’s invoice quotes the PO number, the buyer can match the bill against the order line by line.

PO versus invoice

The two documents are mirror images, separated by time and direction:

Purchase orderInvoice
Sent byThe buyerThe supplier
WhenBefore fulfilmentAfter fulfilment
Says”Please supply this""Please pay for this”

Matching an invoice back to its PO is one of the most common checks in business bookkeeping, which is why a clear PO number matters.

What to put on a purchase order

A useful PO includes:

  • The buyer’s details (you, as issuer) and the supplier’s details (the recipient).
  • A unique PO number, such as PO-0001 or PO-2026-014.
  • The order date, and a delivery date if relevant.
  • Line items: a description, quantity and unit price for each.
  • The subtotal, any tax, and the total.
  • Notes: delivery address, terms, or anything the supplier needs to know.

A word on PO numbers

The PO number is the thread that ties the order, the delivery and the invoice together. It only needs to be unique and easy to trace. A running sequence works, and adding the year (PO-2026-014) makes filing simpler. Suppliers will usually quote it back on their invoice, so keep the format consistent.

To raise one now, open the purchase order generator. It is free, adds no watermark, and nothing you type leaves your browser.

Frequently asked questions

What is the difference between a purchase order and an invoice?
A purchase order is sent by the buyer before goods or services are supplied, to request them at an agreed price. An invoice is sent by the supplier afterwards, to request payment. The two are often matched by PO number so the buyer can check that the bill agrees with what was ordered.
Who creates the purchase order?
The buyer. The PO is the buyer's formal request to purchase, so it carries the buyer's details as the issuer and the supplier's details as the recipient. The supplier then fulfils the order and bills against the PO number.
Is a purchase order legally binding?
Once the supplier accepts it, a purchase order generally becomes a binding agreement to supply the listed items at the stated prices, and for the buyer to pay. That is part of why POs are useful: they put the agreement in writing before anything is delivered.

Ready to try it?

Raise a purchase order and download the PDF. Free, in-browser, and 100% private, your data never leaves your device.

Open the Purchase Order Generator

Related guides

How to Make an Invoice (Step by Step) What goes on an invoice, how to number it, and how to send one that gets paid, with a free generator to do it in your browser. Invoice vs Receipt vs Quote: What's the Difference? A quote asks 'shall we?', an invoice asks 'please pay', and a receipt confirms 'you paid'. Here's how the three documents differ and connect.