What's going on
The "hi mum" scam is exactly what it sounds like. A criminal sends a WhatsApp message or text pretending to be your son, daughter, or another close relative. They say they have a new number because their phone has been lost, stolen, or broken. Once you reply, they tell you they are locked out of their banking app and need you to transfer money to cover a bill. You pay, the money goes straight to the criminal, and by the time you ring your actual child, it's too late.
Santander reported that in the first five months of 2025 alone, more than 500 of these scams cost UK victims a total of £490,606 (Santander UK). Lloyds Banking Group recorded a 2,000 per cent year on year increase in reported cases during 2024, with the average victim losing £1,950 (Lloyds Bank). Action Fraud logged £1.5 million in losses from 1,235 reports over just five months in 2022 (Action Fraud). The numbers keep climbing because the scam is simple, cheap to run, and preys on something no parent can ignore: a message from their child asking for help.
What these messages look like
The opening message is always casual, always warm, and always from a number you don't recognise. These are based on real reports to Action Fraud and UK banks.
"Hi mum its me. I dropped my phone down the toilet and this is my new number. Can you save it and text me back on here? xx"
"I need to pay my landlord today but I cant get into my banking app because it's linked to my old number. Could you transfer £1,200 for me? I'll pay you back as soon as my new sim is sorted. The details are sort code 20-45-67 account 12345678"
"Hey dad, phone got nicked last night. Got a temporary one. Can you WhatsApp me on this number instead? Need to ask you something x"
"Mum I've lost my phone and this is a temporary number. I'm stuck and really need help. Can you send me some money for a new one? I'll explain everything later xx"
Why these messages work
The criminals don't need to know your child's name. "Hi mum" does the work for them. Most parents will reply straight away because they're worried. Once you've replied, the scammer knows you believe them and they move to the money request within minutes. The amounts are usually between £500 and £3,000, enough to make it worth their time but small enough that you might not hesitate too long. Some ask for a second payment the next day.
How the scam works, step by step
The whole thing can play out in under 20 minutes. Here is the typical sequence from start to finish.
1. The first message arrives
A WhatsApp message or text lands on your phone from a number you don't recognise. It says "hi mum" or "hi dad" and tells you their phone is broken, lost, or stolen. They ask you to save the new number. The tone is casual, the kind of message your child would send. Some versions include a kiss at the end or use the nickname your child uses for you if they've done their homework on social media.
Where do they get my number?
Criminals buy phone number lists from data breaches, scrape social media profiles, or simply send the message to thousands of numbers at random. They don't need to know who you are. If they send "hi mum" to 10,000 people, a percentage will have children and a percentage of those will reply. It's a numbers game.
2. You reply and they build the story
Once you respond, the scammer knows the bait has worked. They chat back and forth, keeping it light, asking how you are, making small talk. They avoid phone calls and say they can't ring you because the new phone doesn't have their contacts or their microphone isn't working. The whole point is to get you comfortable before the money request comes in.
They'll dodge a phone call
If you ask to ring them, they'll have an excuse ready. The microphone is broken. They're in a meeting. They're in a library. They'll call you later. Every excuse has the same purpose: stopping you from hearing a stranger's voice. If they can't keep you on text, the scam falls apart.
3. The money request
They tell you they need to pay a bill but can't get into their banking app because it's linked to their old number. They send you a sort code and account number and ask you to make a bank transfer. The reasons vary: rent, a utility bill, a car repair, money for a new phone. Some ask for smaller amounts first (£50 or £100) to test the water before asking for more. The account details they give you belong to a money mule or another criminal, not your child.
4. The money is gone
You transfer the money. Within minutes, it moves through multiple accounts and often ends up converted to cryptocurrency or sent abroad. The scammer may come back the next day asking for more, using a different excuse. By the time you ring your real child and realise what has happened, recovering the money is extremely difficult.
Why recovery is so hard
Because you made the transfer willingly, your bank treats it as an authorised push payment. The money left your account on your instruction, even though you were tricked. Since October 2024, new rules from the Payment Systems Regulator mean banks must reimburse most APP fraud victims up to £85,000, but you still need to report it fast and the bank may argue about the details.
The AI voice note version
Criminals are now cloning your child's voice
From 2025 onwards, UK fraud teams started seeing a new version of this scam. Instead of plain text, the criminal sends a WhatsApp voice note that sounds like your son or daughter. The voice is generated by AI using as little as three seconds of audio scraped from a social media video, a voicemail greeting, or a TikTok clip. The technology is accurate enough to fool parents who have lived with that voice for 20 years. If you get a voice note from an unknown number that sounds like your child, do not trust it. Call them on their real number instead.
Where they get the voice from
Public Instagram reels, TikTok videos, YouTube clips, and voicemail greetings. If your child's voice appears anywhere online, even briefly, it can be cloned. Three seconds of clear audio is enough to produce a convincing copy (DailyAI, 2025).
How to protect against it
Agree a code word with your family that you would use if you ever needed to prove your identity over the phone. Something only you would know. If a voice note asks for money, call the person on their real number before doing anything else. A voice note proves nothing.
How to tell it's a scam
Warning signs
- • Message from an unknown number claiming to be your child
- • Says their phone is broken, lost, or stolen
- • Asks you to save a new number
- • Won't take a phone call (always has an excuse)
- • Asks you to transfer money to a third party account
- • Puts time pressure on you ("needs paying today")
- • Asks for a second transfer shortly after the first
What to do instead
- ✓ Call them on the number you already have saved
- ✓ Ask a question only the real person would know
- ✓ Check with another family member before doing anything
- ✓ Ask for a video call (scammers will refuse)
- ✓ Take your time. A real child can wait an hour for money
- ✓ Agree a family code word for situations like this
- ✓ Never send money to account details given over text
It's not just WhatsApp
The scam has spread to regular text messages
Which? reported in late 2022 that the "hi mum" scam had moved from WhatsApp to standard SMS text messages (Which?). This matters because regular texts don't show a profile picture and there's no way to check when the number was registered. Between 2023 and 2025, Action Fraud recorded £226,744 in losses from "hi mum" and "hi dad" texts sent by SMS rather than WhatsApp (Action Fraud). The same rules apply. If someone texts you from a new number asking for money, ring the old number before you do anything.
Scammers also try to pull people onto WhatsApp from the other direction. Automated calls offering a part-time job and asking you to add the number on WhatsApp surged in 2026. Our guide to "add me on WhatsApp" scam calls explains how they work.
Sent money already? Do this now
Ring your bank immediately
Call the fraud line on the back of your card. Tell them you've made a bank transfer to a scammer and give them the amount, the sort code, and the account number you sent it to. They can contact the receiving bank and try to freeze the money before it's moved on. Speed matters. The faster you call, the better your chances.
Report it to Report Fraud (formerly Action Fraud)
Report the scam at reportfraud.police.uk or call 0300 123 2040. This creates a police record and feeds into the National Fraud Intelligence Bureau. If you live in Scotland, report to Police Scotland on 101 instead.
Ask about the PSR reimbursement rules
If you sent money through Faster Payments on or after 7 October 2024, your bank must reimburse you up to £85,000 under rules set by the Payment Systems Regulator. They may apply an excess of up to £100, but not for vulnerable customers. If your bank refuses or delays, take it to the Financial Ombudsman Service (0800 023 4567).
Report the WhatsApp number
Open the chat in WhatsApp, tap the contact name at the top, scroll to the bottom, and tap "Report". This flags the number to WhatsApp. You can also block them from the same screen. Forward scam texts received by SMS to 7726 (free on all networks).
Where to report
Your Bank
Start here. Call the fraud line on the back of your card. They can try to recover the money and begin the reimbursement process.
Report Fraud
The national fraud reporting service for England, Wales, and Northern Ireland
Report the scammer's account directly within WhatsApp
Open the chat > tap the contact name > Report7726 (SMS Spam)
Forward scam text messages to 7726. Free on all UK networks. Your provider investigates and can block the sender.
Frequently Asked Questions
My child really has lost their phone. How do I know if a message is genuine?
Will my bank refund me if I fell for this?
Can criminals really clone someone's voice from a short clip?
Are older people more at risk?
What should I do if I replied but didn't send money?
Quick Summary: Stopping "Hi Mum" Scams
- Always call the original number before sending money
- If they won't take a phone call, it's a scam
- Ask a question only the real person could answer
- Voice notes can be faked with AI
- Agree a family code word for emergencies
- Never transfer money to account details sent by text
- If you've paid, call your bank straight away
- Talk to older relatives about this scam