Procurement 3-way match assistant: a playbook (PO, GRN, vendor bill)

3-way match is where procurement meets accounting reality.

If you treat it as “auto-match with AI,” you will ship duplicates and disputes.

Start here:

• AI procurement 3-way match assistant
• Accounts payable
• GRN software
• Vendor bills

Step 1: Make evidence linkage the default

For each match candidate, link:

• the PO
• the GRN evidence (received quantities)
• the vendor bill document

If evidence is missing, fail closed and route to a queue with reasons.

Step 2: Define reason codes for exceptions

Examples:

• quantity mismatch
• unit mismatch
• missing PO reference
• partial delivery
• missing evidence

Reason codes are what make the queue actionable.

Step 3: Keep approvals explicit for money actions

Bills and payments should remain approval-gated:

• Approval policies
• Approval matrix

Step 4: Make reruns safe

Vendors resend updated bills.

Your workflow must support safe reruns:

• deterministic behavior
• preserved audit trails
• no duplicate side effects

Related:

• Safe retries and idempotency
• Audit logs