In short
A message from a new number says it's your child and asks for money. How the Hi Mum scam works and how to check who you're really talking to.
Top warning signs: A new number and a reason not to call; Asking you to delete the old number; An urgent payment to someone else's account.
First thing to do: Stop and call your relative on the number you already have saved, even if the message says that phone is broken.
How the scam works
Scammers message thousands of numbers with the same opening. They don't know who you are. They wait for someone to reply “Is that you, Sophie?”, and then they become Sophie.
The story is always why they can't just call: a broken microphone, a lost phone, being at work. Then there's a bill due today, and they can't pay because of the new phone. The account details are usually a stranger's name, explained as “a friend's account” or “the landlord”.
If you pay, a second or third request often follows. With AI voice cloning, some versions now include a short voice note that sounds like your relative.
Red flags to look for
- A new number and a reason not to call. Anyone who's really your child can take a 10-second call or answer a question only they'd know.
- Asking you to delete the old number. This stops you from checking with the real person.
- An urgent payment to someone else's account. Real family members rarely need money sent to a stranger's name today.
- Pet names but no real details. They say “Mum” or “Dad” but avoid names, places or shared memories.
What to do if you get one
- Stop and call your relative on the number you already have saved, even if the message says that phone is broken.
- Ask a question only they'd know, or ask for your family safe word. Set one up in two minutes.
- Report the number inside WhatsApp (open the chat → tap the name → Report) and block it.
Why it works so well
It skips every technical defence. There's no link to block and no virus to detect. It works on love and a sense of duty. That's why a simple family rule helps more than any app: no money moves until we've spoken on a known number.
If you already paid or shared details
Act quickly. It makes a difference.
- Call your bank immediately. The faster you report, the better the chance of stopping or recovering the payment.
- Report it to the police or your national fraud reporting service, and keep screenshots of the chat.
- Warn other family members. Scammers sometimes try the same trick on grandparents or siblings.
More help: what to do after a scam, and where to report it in your country.
Questions people ask
The voice note sounded exactly like my son. Could it still be fake?
Yes. AI can copy a voice from a few seconds of audio taken from social media videos. Always verify with a call to the known number or a safe word.
Should I reply to see who it is?
Don't reply. Check with your family directly instead. Replying tells scammers your number is active.
Official sources and further reading
We check our guides against advice from government agencies and consumer protection bodies.
- ACCC warning of suspicious messages as "Hi Mum" scams spike (Scamwatch, Australian Competition and Consumer Commission)
- How to spot a WhatsApp family impersonation scam (Police Service of Northern Ireland)
- 'Friend in need' scams cost WhatsApp users 1.5 million pounds (Action Fraud, UK police)