What Is 3-Way Matching?
3-way matching is an accounts payable control that compares three documents — the purchase order, the goods receipt, and the supplier invoice — to verify that a business is only paying for what it ordered and actually received. If all three agree, the invoice is approved for payment; if they don't, it's held for investigation.
What 3-way matching is and why it matters
The three documents each answer a different question: the purchase order says what was authorized, the goods receipt (or delivery note) says what arrived, and the invoice says what the supplier is charging. Matching them catches the classic AP failure modes — duplicate invoices, price creep above the agreed rate, billing for quantities never delivered, and outright fraudulent invoices. It's a standard internal control in any business with meaningful purchasing volume, and auditors expect to see it. The trade-off is effort: done manually, matching is document-shuffling at scale, which is why many small businesses skip it and absorb the leakage.
A worked example
A company issues a purchase order for 100 chairs at $50 each ($5,000). The warehouse logs a goods receipt for 90 chairs — ten were back-ordered. The supplier then invoices $5,000 for 100 chairs. A 3-way match flags the mismatch: the invoice bills 100 units but only 90 arrived. AP short-pays or requests a corrected invoice for $4,500, and the remaining 10 chairs are matched when they ship. Without the match, the company would have overpaid $500.
How firms handle it today
Most teams match by hand: pulling the PO from one system, the delivery note from an inbox or warehouse log, and the invoice from a PDF, then eyeballing quantities and prices line by line. It's slow, and under time pressure the control is often applied only above a dollar threshold — or quietly skipped.
How OCTA Flow relates to 3-way matching
OCTA Flow performs the match automatically as bills arrive — comparing invoice lines against the PO and receipt, routing clean matches to payment, and flagging exceptions with the specific discrepancy for your team to resolve.
Related terms
- Accounts payable
- Purchase order
- Invoice
- Vendor
- Goods receipt
FAQ
What are the three documents in 3-way matching?
The purchase order (what was authorized), the goods receipt (what was delivered), and the supplier invoice (what's being charged).
What's the difference between 2-way and 3-way matching?
2-way matching compares only the invoice and purchase order; 3-way matching adds the goods receipt, confirming the items were actually received before payment.
When does an invoice fail a 3-way match?
When quantities, prices, or terms disagree across the documents — for example, an invoice billing more units than were received or a unit price above the PO rate.
See how firms automate AP matching → start an OCTA Flow trial.