A spending limit is useful, but it cannot explain every unusual payment. A small invoice to a newly changed bank account may deserve more attention than a larger, routine payment to a long-standing supplier.
Map the Reasons for Review
Ask the finance team which situations currently make them pause. Examples might include a new supplier, amended payment details, an unexpected currency or an invoice outside the normal purchasing process. Treat these as prompts for designing your own controls, not as a complete fraud-detection rulebook.
Write the reason beside each approval request. Reviewers should not have to hunt through several emails to understand why a transaction has reached them. The request should include the relevant supporting record and a clear action: approve, return for clarification or reject.
Decide Who Can Change the Rules
An approval process loses value if the same person can quietly alter its settings and approve the resulting payment. Identify who maintains limits, supplier records and user access. Keep a reviewable record of changes and decide how absence or staff turnover will be handled.
The details depend on the business and its systems. Ask your finance adviser and providers to check the proposed arrangement where necessary. This is a workflow-design guide, not a statement of legal compliance requirements.
Include the Failed Transaction
A workflow should explain what happens after an approval as well as before it. If a payment is rejected or its outcome is uncertain, who checks the status? When is a retry allowed? How does the original approver learn that the transaction changed?
Visa's agent-payment pilot illustrates why identity and authorisation become more visible when software executes a transaction. Visa agent-payment pilot and controls Those questions are equally useful when a person operates the portal.
Run a Tabletop Trial
Take five fictional invoices and walk them through the process with the staff involved. Include a missing document and an urgent request made outside normal hours. Note where people disagree about responsibility. Resolve that ambiguity before adding automation. A well-designed process makes the unusual case understandable instead of leaving it to the most confident person in the room.