Three-way match
An accounts-payable control that requires the supplier invoice to match both the purchase order and the goods-receipt note on key fields before payment is approved.
Three-way matching is the canonical AP control: invoice, purchase order, and goods receipt must agree on vendor, item, quantity, and (optionally) price. The third leg — the goods-receipt note (GRN) — provides independent confirmation that what was ordered was actually delivered before the supplier is paid.
The control catches several distinct fraud and error modes: supplier invoicing for items never delivered, quantity over-billing, billing for items at a higher price than agreed, and duplicate invoices. Three-way matching is a SOX-relevant control in many regulated environments and is typically required for inventory-affecting purchases.
Three-way reconciliation can produce many exception types: quantity received less than invoiced (short shipment), price on invoice higher than PO (price variance), receipt without an invoice (received not invoiced or RNI), and invoice without a receipt (invoice not yet received against the goods, or GRIR). Each has its own resolution path and ageing implications.