What to do when a supplier invoice is wrong

Why not to delete it

A wrong invoice is still a document that arrived. Deleting it solves the discomfort and erases the trail, and then there is no way to explain why the supplier believes they are owed money and you believe they are not.

The supplier deleted nothing at their end. There the invoice exists, numbered and recorded. When the two of you disagree about what happened, whoever holds the record runs the conversation.

And why not to pay only the correct part

A partial payment with no document explaining it looks like an open debt at the supplier’s end. It stays on their ledger, comes up in the next collections call, and eventually somebody pays it to close the matter.

The partial payment is not the problem. The problem is a partial payment with no document beside it saying why.

What to do instead: a credit note

A credit note is a document in its own right, linked to the invoice it came from, with the reason it was opened. It stays open until the money returns or until it is offset against the next invoice.

• The number of the original invoice it refers to
• The reason, in language that will still make sense in six months
• The amount, and if it is partial, exactly what for
• Who approved it at your end

The first three are what the supplier needs. The fourth is what you will need, and it is the same record that turns an approval into a process rather than into one person’s discipline.

What to ask the supplier for

It depends what is wrong. If the price or quantity is wrong and the invoice is already recorded at their end, the request is a credit note. If it has not been recorded yet, it is sometimes simpler to ask them to cancel and reissue.

The difference is not only technical. A credit note leaves both documents in the record and the history intact; a cancel and reissue leaves one clean document, and also erases the fact that there was an error. The third time the same supplier makes the same mistake, that history is worth something.

How to know the money really came back

This is the question that most often falls through, because a credit note feels like the end of the process and it is only the promise of one.

A closed credit is one whose money was seen: either returned by transfer, or offset against a later payment you can point to. Until then it is open, even if the supplier has already said they dealt with it.

That is why bank reconciliation is not an accounting chore at the end of the month but the part that closes the loop. A payment, a credit or an offset that has not been matched against a real transaction is still a promise.

And if it keeps happening

Then it is no longer a mistake but a pattern, and it is handled somewhere else: in the price list and the order, not in the invoice.

A supplier who repeatedly charges above the list is usually working from a more recent list than yours. A supplier whose deliveries are repeatedly short is usually packing to availability rather than to the order. Both are solved by one conversation about the expectation, rather than five conversations about five invoices.