Insights · Published 8 November 2026
One of the most expensive scams a business can fall for needs no hacking skill at all. A message arrives that looks like it is from a supplier you pay every month. It says their bank details have changed, and asks you to send the next payment to a new account. Your accounts team updates the details, pays the invoice, and the money is gone. Weeks later the real supplier calls to ask why they have not been paid.
This is usually called invoice fraud or payment diversion. It works because it looks routine. The good news is that it is also one of the easiest frauds to stop, with a few habits that cost nothing.
How it reaches you
The message can come in several ways. Sometimes the criminal has broken into your supplier's email and sends the request from their real address, often replying inside a genuine email thread. Sometimes they register an address that looks almost the same, with one letter changed. Sometimes it comes by WhatsApp from a new number with the supplier's logo as the profile picture, saying the old phone was lost.
There are MoMo versions too. A message claims to be from a supplier, a landlord or a staff member, asking you to send payment to a different mobile money number "just this once". Or a caller claims to be from your bank or network and asks for a code. The pattern is always the same: a change to where money goes, with a reason and some urgency.
The warning signs
Train everyone who handles payments to stop and check when they see any of these.
- A request to change bank or MoMo details, whatever the reason given
- Pressure to pay today, or a warning that delivery will stop
- A new phone number, or a request to reply only by WhatsApp
- A slightly different email address or a new personal email account
- An account name that does not match the business name
- A request to keep the change quiet or not to call
The one rule that stops it: call back on a number you already have
Whenever anyone asks to change payment details, call the supplier before you change anything. Use a number you already had on file, from an old invoice, your contract or your supplier list. Never use the phone number in the message asking for the change, because that number belongs to the criminal.
Speak to someone you know at the supplier and ask them to confirm the new details. If they did not send the request, you have just saved the payment. If they did, you have lost five minutes. Write down who you spoke to and when.
Do the same for MoMo. If a staff member or supplier suddenly wants money sent to a new number, call the number you have always used for them.
Two people for every change and every large payment
Most fraud succeeds because one person can change the details and send the money alone. Split those jobs. One person enters or changes a supplier's bank details, and a second person checks and approves the change after the call-back. For payments above an amount you choose, require a second approval before the money leaves.
Most business banking platforms let you set up dual approval for payments, and many accounting systems log who changed a supplier record. Ask your bank and your accountant to help you switch these on. It feels slow for a week, then it becomes normal.
Protect your own email too
Criminals often get into a mailbox, read it quietly for weeks, and then strike when a big invoice is due. That mailbox could be yours, and your customers could be the victims. Turn on two-step verification for every email account, use strong unique passwords, and check for strange forwarding rules. A business email on your own domain also makes lookalike addresses easier to spot.
Tell your customers how you will and will not contact them. A simple line on your invoices, saying that you will never change your bank details by email or WhatsApp and asking them to call you to confirm, protects them and your cash flow.
If it happens
Speed matters. Call your bank immediately, using the number on its website or your card, and ask them to try to stop or recall the payment. Contact the receiving bank or the mobile money provider as well. Report it to the police. Then change the passwords on any email accounts involved and check them for forwarding rules. Keep the messages as evidence, do not delete them.
Recovery is not guaranteed, which is why the checks above matter so much more than the clean-up.
Your checklist
You can put most of this in place this week.
- Write a one-line rule: no payment detail changes without a call-back on a known number
- Keep a verified supplier contact list that is separate from email
- Require two people for detail changes and for payments above a set amount
- Ask your bank to switch on dual approval in business banking
- Turn on two-step verification for every mailbox that handles invoices
- Add a line to your invoices telling customers how to verify your details
- Brief your accounts and admin staff, and repeat it every few months
Dalysie Ghana can run a short briefing for your accounts team and help you secure the email accounts behind your payments.