Guide
The Hi Mum scam: what it is and how to beat it
It works because it aims at love, not at greed. One phone call defeats it.
Updated 9 July 20266 min readBy AngusPart of Online safety tips
The Hi Mum scam is a text message from an unknown number claiming to be your child or another family member: hi mum, I lost my phone, this is my new number. It feels personal, it lands at busy times, and it has cost Australian families millions because it aims at love rather than greed.
This guide covers how the scam unfolds message by message, the one habit that defeats it every time, and exactly what to do if money has already been sent.
How the scam unfolds, message by message
The pattern is remarkably consistent, because it is a script.
- The opener: a message from an unknown number claiming to be your child. Lost or broken phone, this is the new number. Often just: Hi Mum.
- The warm-up: ordinary chat to build comfort. How are you, sorry about the hassle. Some versions skip this entirely.
- The problem: because the phone is new or broken, they say they are locked out of their banking app.
- The ask: an urgent bill or payment that cannot wait, with account details for a transfer. The account belongs to the scammer.
- The push: if you hesitate, pressure or guilt. Please mum, I would not ask unless it was urgent.
The one habit that defeats it
Call the old number. Not the new one in the message, the number you already have saved for that person. Almost every version of this scam collapses at that single step, because either your real child answers on their usual phone, or you leave a message and hear back soon.
If calling is not possible, ask the new number a question only the real person could answer. Not their birthday or pet's name, which can be found online, but something like what did we have at lunch on Sunday. A scammer changes the subject or pushes harder on the money. A real family member just answers.
Good to know
- Agree on a family code word before it ever happens. Any urgent money request by text must include it. This one dinner-table conversation protects the whole family.
Why smart, careful people fall for this
Nobody falls for this because they are foolish. It works because the story is plausible, phones do break and numbers do change, and because worry about your child overrides the checking instinct. Scammers send thousands of these knowing a handful will land at exactly the wrong busy moment. Being caught is not a failure of intelligence, which is also why the defence is a habit, not cleverness.
If money has already been sent
Speed matters far more than embarrassment. Bank transfers can sometimes be stopped or traced if the bank is told quickly.
- Phone your bank immediately on the number on the back of your card. Tell them it is a scam payment and ask them to attempt recall.
- Report it to Scamwatch at scamwatch.gov.au and to ReportCyber at cyber.gov.au.
- Keep the message thread as evidence. Do not delete it.
- Tell the family member being impersonated, so they can warn others in their contacts.
Good to know
- For the full ordered response, including securing accounts and IDCARE on 1800 595 160 if identity details were shared, see our guide on what to do if you have been scammed.
Variations to watch for
The same script arrives as Hi Dad, or claims to be a grandchild, and it runs on WhatsApp as well as SMS. Newer versions use voice messages, and scammers are increasingly able to clone a familiar voice from clips found online, so a voice alone is no longer proof. The defence does not change: contact the person on the number you already have, or use the code word.