SIM swap scam: what to do fast
Your number has stopped working and someone else may now be receiving your messages.
Updated 2026-09-29 · Independent resource. Legal review pending.
What a SIM swap actually is
A SIM swap moves your phone number onto a new SIM card that the scammer controls, often after they have gathered enough of your personal details to convince your telco it is a genuine request. Once it works, your own SIM stops receiving calls and texts.
The number itself is not the target. The one-time passwords and account alerts that arrive by text message are, since they can unlock banking, email, and anything else tied to that number.
This is why a SIM swap so often leads directly into account takeover within a short window of time.
How you usually find out
The clearest sign is a sudden, complete loss of signal, with no explanation and no network outage in your area. Calls and texts stop arriving entirely, not just slow down.
Around the same time, you may see account alerts, login notifications, or password reset messages you did not request, arriving on another device the scammer controls. If you can still reach your email from a computer or another device, check it immediately.
Do not assume a technical fault first if this happens without warning. Treat it as a live security event from the start.
Contact your telco and bank fast
Call your telco’s fraud or customer line from another phone, or visit a service counter with identification, and report the swap as fraud rather than a technical issue. Ask them to block the fraudulent SIM and restore your original number.
At the same time, contact your bank to flag your account for a possible SIM swap, since they can watch for or block transactions that rely on text-based one-time passwords.
If money has already moved, call the National Scam Response Centre on 997, since a recent transfer is more likely to be stopped in time.
What to do next
Once your number is restored, change the passwords on your banking, email, and any account that uses text messages for verification, doing this from a device you trust. Switch to an authenticator app for one-time passwords where your bank offers it.
If a transaction went through while you were locked out, read how a bank recall works and consider making a police report to support any dispute.
Keep a short record of when the signal dropped and when it returned, since that timeline is useful evidence if you need to escalate the matter later.
If your number has stopped working and you suspect a SIM swap, message us with what you have noticed and we will help you work out what to secure first.
Common questions
My phone suddenly has no signal. How do I know if this is a SIM swap?
A sudden, total loss of signal with no explanation from your telco is the main sign, especially alongside account alerts you did not trigger. If this happens without warning, treat it as urgent rather than waiting to see if it resolves itself.
Why does losing my SIM put my bank account at risk?
Banks often send one-time passwords by text message, so whoever controls your number can receive them instead of you. That access is usually the real goal of a SIM swap, not the phone number by itself.
How do I get my number back?
Contact your telco directly, ideally at a service counter with identification, and report the swap as fraud. Once your number is restored, change your banking and email passwords straight away, since the same access may have reached other accounts.
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Read thisIf your number has stopped working and you suspect a SIM swap, message us with what you have noticed and we will help you work out what to secure first.