Short answer
Treat any message from a family member or friend on a new number who needs money urgently as a scam until you have checked it. Call the number already saved in your phone — if they answer, it is a scam. If you can’t reach them, try another way, ask a question only they could answer, or ask for a voice call. Never send money or codes until you are certain. Report the number in WhatsApp (press and hold the message → Report) and block it. If you have already paid, call your bank immediately and report it to the police.
How the scam works
- A message arrives — usually on WhatsApp — from someone claiming to be your child, parent or friend: they lost or broke their phone and this is their new number.
- After a few friendly messages comes the request: an urgent bill, a payment to a contractor, a new phone — and their online banking “isn’t working”, so could you pay it.
- Some messages just say “it’s me”; others use the real name of the person being impersonated.
- Sometimes they ask for photos or personal details instead of money, to use in the next scam.
The one-call check
- Stop. Don’t reply with money, codes or personal details.
- Call the number you already have saved for that person. If they pick up, you have your answer.
- If you can’t reach them, use another channel — another family member, their partner, their workplace.
- Still unsure? Ask a question a stranger couldn’t answer, or ask for a voice call or voice note. Scammers avoid both.
When the message comes from a contact you know
The same script also comes from real numbers: a friend’s WhatsApp is taken over, and the attacker messages everyone in their contacts and groups. A known name is no guarantee — call before you pay. To stop it happening to you, turn on two-step verification and never share the six-digit WhatsApp code, not even with friends; see WhatsApp hacked.
If you have already paid or shared details
- Call your bank straight away and ask them to stop or recall the payment.
- Report it to the police — in England, Wales and Northern Ireland through Report Fraud; elsewhere see where to report, by country.
- If you shared personal or identity details, contact an identity-support service such as IDCARE in Australia.
- Expect a second wave: victims are often targeted by “money recovery” scams promising to get the money back for a fee.
Protect your family
- Tell parents and grandparents about the script — it works because it is plausible.
- Agree on a family rule: no money for a “new number” without a voice call.
- Turn on two-step verification on every family member’s WhatsApp.
- If someone’s account was taken over, our hacked account recovery service helps them get it back through WhatsApp’s official route.
Frequently asked questions
Is the Hi Mum scam only on WhatsApp?
Mostly WhatsApp, but the same story arrives by text message too. The defence is the same: call the number you already have.
Can my bank get the money back?
Sometimes, if you call quickly. Banks can try to stop or recall a payment; the sooner they know, the better the chance.
Should I reply to test whether it is real?
No. Don’t engage — call the saved number instead. Replying only tells the scammer your number is active.
How do scammers know my child’s name?
Contact details leak through data breaches and hijacked accounts. Scamwatch notes that some messages use the real name of the person impersonated.
Sources: Scamwatch (ACCC) — “Hi Mum” scams warning, Action Fraud — fake text messages targeting parents, Action Fraud — WhatsApp group chats targeted by fraudsters, Report Fraud — how to report suspicious messages, WhatsApp Help Center — recover a compromised account