Approving an invoice is not the same as approving the spend. The spend was agreed months ago, by somebody else, possibly verbally. What is being asked now is narrower and harder: is this bill correct, and should we pay it?
The question
This is the check almost nobody builds, and the only one that catches real money.
An invoice approval that only asks is this the right budget code catches coding errors and nothing else. The expensive mistakes are a supplier billing for eleven when nine were delivered, a monthly charge for a service cancelled in March, and the same invoice arriving twice with different reference numbers.
All three are caught by the same person: whoever received the thing. They are also the person least likely to be in the approval, because approvals get routed by seniority rather than by knowledge.
Put the receiver first and the budget holder second. It costs one extra step and it is the only step on this page that finds money.
The build
The columns matter more than the automations.
Attach both documents. An approver holding only the invoice cannot answer whether it matches what was ordered, so they approve the number they can see. Two files in the same request turn a rubber stamp into a comparison.
What gets asked later
Six months on, with a supplier disputing the amount.
monday’s activity log records that somebody moved a status to Approved at a time. It does not record which file was attached when they did it — and invoices get replaced more often than any other document on a board, because suppliers reissue them with a corrected amount, a new date or a different reference.
The result is an item showing an approval and an invoice that nobody approved. It is not fraud and it is not usually anybody’s fault; it is a file being replaced quietly by a process that has no opinion about it.
Never overwrite an invoice. Add the reissued one beside it with the date in the filename. It costs nothing and it is the difference between answering that question and guessing at it.
The boundary
Worth being clear about before you build a month of work on it.
A monday board can hold the decision, the documents and the record of who agreed. It does not post a journal, it does not know your payment terms, it does not stop a duplicate payment, and nothing here touches a bank.
That is a reasonable place to stop for most companies below a few hundred invoices a month — the approval is the part that involves people and is therefore the part that goes wrong. Past that, the volume belongs in an AP system and the board becomes a second place to keep in sync.
Questions
You can run the approval — who has to agree, in what order, and the record of it — on a monday board, and plenty of companies do. What monday does not do is pay anything or post to your ledger: the approval ends with somebody in finance being told it is cleared, and payment happens wherever payments happen.
Three things, in this order: that the goods or work actually arrived, that the amount matches what was agreed, and that it is coded to the right budget. Most approval processes only ever check the third, because it is the one visible on the screen in front of the approver.
The person who received the goods or work, because they are the only one who knows whether it arrived. Sending it to whoever signs off spend is common and mostly theatre — a director looking at a line and a number has no way of knowing whether the pallet turned up.
A number column and one conditional automation per threshold: when the status changes and the amount is over a value, notify the person for that band. It works and it grows awkwardly — four bands means editing every automation whenever a threshold moves.
What we built
And the approval reopens if either is replaced.
Signoff previews both documents inside the request rather than linking them, so the person approving is comparing rather than trusting. Every decision records which documents that person had actually opened.
If a supplier reissues the invoice after somebody approved it, the approval reopens and the earlier decision is kept, struck through, as the record of what was agreed to. That is the exact failure described above, and it is the reason this app exists.
Keep reading
The difference between approving a contract and signing one, surviving four rounds of redlines, and why every new version invalidates the last approval.
Why no app can live on a subitem card, what a status column on the subitem board does and does not do, and how to get a sign-off recorded against one anyway.
One board, one status column, and one automation per transition.
Three approvals a month, free. Attach the invoice and the order, approve it, then replace the invoice and watch what happens.