Questions to Ask a Vendor When Invoice Details Do Not Match

1. PO reference: Which purchase order or agreement does this invoice relate to? 2. Price difference: Why does the unit price differ from our order or contract? 3. Quantity difference: What quantity was shipped or delivered, and when? 4. Duplicate or revision: Is this a new invoice, a revision, or a resubmission of an earlier one? 5. Invoice number: Can you confirm the invoice number and date? 6. Bill-to entity: Which of our entities was this invoice issued to? 7. Remit-to and banking: Have your remit-to or banking details changed recently? 8. Tax: How was tax calculated, and which jurisdiction applies? 9. Supporting evidence: Can you provide the contract, proof of delivery, or revised invoice?

When the invoice does not match a purchase order, start by confirming which PO or agreement it relates to. A mismatch often traces back to the wrong PO reference, a PO that was never created, or an invoice that should have been billed against a different order.

For price and quantity differences, ask why the figures differ from the order and what was actually shipped or delivered. A higher price may reflect a change the vendor made without approval, and a quantity difference may reflect a partial delivery, a backorder, or an error. The vendor's answer determines whether the invoice can proceed, needs a credit, or should be corrected.

When an invoice looks like one you have already seen, ask the vendor directly whether it is a new invoice, a revision, or a resubmission. Vendors sometimes resend an unpaid invoice with a slightly different number, which can look like a separate bill.

Confirming the invoice number and date against your records, and asking the vendor to clarify, prevents a duplicate payment. If it is a revision, ask which earlier invoice it replaces so the original can be closed cleanly.

A mismatch in remit-to or banking details deserves special care, because changed payment instructions are a common fraud vector. Ask the vendor whether their details changed, but do not act on the answer that arrives on the invoice or in the same email thread alone.

Standard practice is to confirm any change to banking or remit-to information through a separate, previously verified channel, such as a known phone contact. The question to the vendor is part of the check, not the whole of it.

Stampli centralizes invoice communication on the invoice itself, so questions to the vendor and their answers stay attached to the transaction instead of living in separate inboxes. The document, comments, coding, and approval history are in one place when a discrepancy needs to be resolved.

A vendor portal lets vendors submit invoices and documents directly, which gives AP a consistent channel for resubmissions, revisions, and supporting evidence. Stampli vendor management holds enriched vendor records, contract terms, and interaction history, so the reviewer can compare the invoice against what is on file.

Every action is captured in an immutable audit trail with full context. When a discrepancy is raised and resolved, the exchange and the resolution are recorded, which supports both the payment decision and the later audit.