Invoice Approval & GRN (Goods Receipt Note): The Complete Guide

What a goods receipt note confirms

When goods or services arrive, whoever receives them records a goods receipt note (GRN) — a simple document confirming what actually showed up: quantity, condition, and any visible discrepancies against what was ordered. For services, this might be a sign-off confirming the work was completed as described, rather than a physical inspection.

The GRN matters because it's independent evidence of delivery, separate from what the supplier claims on their invoice. Without it, invoice approval is just trusting the supplier's word that everything arrived as billed.

Three-way matching, step by step

Three-way matching compares three independent records before payment is released:

1. Purchase order — what was ordered, at what price
2. Goods receipt note — what actually arrived
3. Supplier invoice — what the supplier is billing for

If all three agree — same quantity, same price, same items — the invoice clears for payment. If any one disagrees with the other two, that's flagged before payment goes out, not discovered afterward when it's much harder to recover an overpayment. This is the core control that prevents a business from paying for goods that never arrived, or paying a price higher than what was originally agreed.

How invoice approval typically works

Once an invoice passes three-way matching, it usually still needs a human approval step before payment — particularly for larger amounts. A typical flow looks like: invoice received, matched against PO and GRN automatically or manually, routed to the appropriate approver based on amount or category, approved (or flagged for review if there's a discrepancy), then queued for payment according to agreed terms.

The approver's job at this stage isn't to re-verify the whole transaction — that's what matching already did — it's to confirm the spend is legitimate and properly coded to the right budget before it's paid.

Where this process usually breaks

In our research talking to finance and procurement teams, the most common breakdown isn't fraud or major error — it's simple delay. A GRN never gets logged because whoever received the goods didn't know they were supposed to record it. An invoice sits waiting for a match that can't happen because the receipt confirmation is missing, and it stalls in someone's queue for a week. Multiply that across dozens of invoices a month, and the "quick" approval process becomes a real drag on supplier relationships — nobody enjoys chasing a late payment that was actually stuck in an internal process failure.

The fix is rarely more approval steps. It's usually tighter, faster capture of the GRN at the point of receipt, and automated matching that flags discrepancies immediately rather than after someone happens to notice. That's most of what dedicated procure-to-pay software is actually built to do — not replace human judgment on approvals, but remove the manual matching and chasing that slows everything down before a human ever needs to look at it.