What is a purchase order?
What is a purchase order?
A purchase order (PO) is a document a buyer sends to a supplier to order goods or services at agreed prices and terms. It's the buyer's official request to purchase - and it comes before the invoice. Once the supplier accepts your PO, it becomes a binding agreement covering the items, quantities and prices you both agreed. Each PO carries a unique number, so both sides can track the order from request through to delivery and payment.
Purchase order vs invoice
You (the buyer) issue a purchase order to request goods; your supplier issues an invoice to request payment once they've been delivered. The PO comes first and sets the terms; the invoice comes last and bills against them. They usually share the same PO number so they can be matched.
Types of purchase order
– Standard - a one-off order where you know the items, quantities, price and delivery.
– Planned - items, quantities and price are set, but the delivery date or location is confirmed later.
– Blanket - a standing agreement to buy over time, often at a negotiated price, up to an agreed limit.
– Contract - a formal contract of terms that individual purchase orders then reference.
What a purchase order should include
– A unique purchase order number; your and your supplier's details; order, delivery date & location; item descriptions, quantities & unit prices; the total, discounts & taxes; payment terms; billing address if different.