In procurement, three terms get thrown around as if they are the same thing: purchase order, supplier invoice, and purchase entry. They are not. Knowing the difference is the key to a clean buying process — and to stock and books that agree.
Purchase order — your intent to buy
A purchase order (PO) is your document. It says: "We want to buy these items, at these prices, from this supplier." It is created before the goods arrive and before any bill exists. A PO sets expectations, locks in agreed prices, and is what you match everything else against later.
Supplier invoice — the supplier's bill
A supplier invoice is their document. It is the bill the supplier sends you, stating what they delivered and what you owe. You do not create it — you receive it. Your job is to check it against the PO and the goods you actually received.
Purchase entry — recording it in your system
A purchase entry is the act of recording the purchase in your own books — turning the supplier's bill and the received goods into a transaction that updates your stock and your ledger. This is the step that makes the purchase "real" inside your business: inventory goes up, a payable is recorded, and cost of goods is captured.
How they connect
A clean flow looks like this:
- Purchase order — you commit to buy.
- Goods received — stock physically arrives.
- Supplier invoice — the supplier bills you.
- Purchase entry — you record it; stock and ledger update.
Matching the PO, the received goods, and the invoice (a "three-way match") is what stops you from overpaying or paying for goods you never got.
Where AI fits
The slowest, most error-prone step is usually typing the supplier invoice into your system. This is exactly where AI document capture helps: upload the supplier's invoice and the system extracts the line items and tax into a draft purchase entry you review and approve — no manual re-keying, with a human still in control.
How BIZA handles it
BIZA App covers the full chain — purchase orders, RFQs, supplier quotations, and purchase entries — with stock and ledger updated automatically and AI capture for supplier invoices. See our inventory and procurement features or talk to the team.