Invoicing glossary
Purchase order
A purchase order (PO) is a document a buyer sends to a seller to authorize a purchase, listing the items, quantities, and agreed prices.
Purchase order: a clear definition
The purchase order comes first: the buyer commits to buy. The invoice comes after delivery: the seller requests payment. Many businesses require a PO number on the invoice so it can be matched and approved — a process called PO matching.
How Invco helps
Invco is an AI invoicing assistant that handles purchase order and the rest of your billing for you. Design a custom invoice template, then let Claude create and send invoices on it in plain English — with subtotals, tax, and totals calculated automatically and every invoice tracked from sent to paid. Start free with one company.
- Related terms: Proforma invoice, Invoice number
Frequently asked questions
What is purchase order?
A purchase order (PO) is a document a buyer sends to a seller to authorize a purchase, listing the items, quantities, and agreed prices.
What is proforma invoice?
A proforma invoice is a preliminary bill of sale sent before work or delivery, showing the expected cost — it is not a demand for payment.
Invoice the easy way with Invco
Let an AI assistant create and send your invoices on a template that looks like your brand. Start free with one company — no credit card required.
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