Start with the shape of the call
Legitimate callers who need you generally leave a voicemail, send an SMS, or try again within the hour. Callback-bait rings once or twice, leaves nothing, and often arrives outside business hours.
- Rang once, no message, odd hour: do not call back before checking the number.
- Rang and left a voicemail with a company, a reference and a reason: usually genuine.
- Repeated calls from slightly different numbers in the same range: a dialler, not a person.
- An international prefix you do not recognise, when you know nobody overseas: leave it.
Wangiri callback fraud
'Wangiri' means 'one ring and cut' in Japanese, and it names the oldest version of this trick: the caller hangs up deliberately so that curiosity does the work. The return call is routed to an expensive premium or international destination, and the charge lands on your bill rather than in a bank transfer, so it can go unnoticed for a month.
The defence is simply not to return unexplained one-ring calls. Nothing important is ever communicated by making your phone ring once.
How to check the number in a minute
Search the number itself before you dial it. If it belongs to a dialler, other Australians have usually already written it down, because these campaigns call thousands of people in the same week. A number with a page full of 'rang once, hung up' reports needs no further investigation.
If there are no reports, judge it by the format: a 190x prefix is premium-rate, a 1300 or 1800 is a business line, a mobile or geographic landline is a person or a company you may genuinely know.
If you decide to call back anyway
Do it from a phone plan you can check, keep the call short, and never respond to keypad prompts, 'press 1 to be removed' menus, or requests to confirm your name. Confirming that a human answers is exactly what a dialler is testing for, and it raises the number of calls you receive rather than lowering it.
Where to report it in Australia
Reporting a call twice — once officially, once publicly — is what stops the next person answering it.
- Scamwatch (run by the National Anti-Scam Centre) at scamwatch.gov.au collects scam reports and publishes national trends.
- The Australian Cyber Security Centre at cyber.gov.au handles cybercrime reports, including phishing links sent by SMS.
- Your bank's fraud line, immediately, if any account, card or code was discussed.
- The number's page on NumberCheck, so the next Australian who searches it sees your experience straight away.