SIM swap: has my SIM card been taken over?
In a SIM swap a scammer has your phone number moved to their own SIM card — by convincing your provider they are you. From that moment they receive your SMS codes. The first sign: your phone has no signal while others do.
SIM swap is rare but serious, because many services still use an SMS code as the second step. Whoever has your number can reset passwords, log in to your bank, and take over WhatsApp. The scammer first collected your details — through phishing, a data breach or social media — and then calls your provider.
The good news: it is quick to recognise, and with two settings almost impossible.
How to spot it
- 1No signal, for no reason.“No service” or “emergency calls only” in a place where you always had signal, while others do.
- 2A text from your provider about a “new SIM card” or “transfer” you did not request.This is the moment to call immediately.
- 3Password reset e-mails you did not request.Google, Apple, your bank, social media: someone is trying to get in.
- 4Friends receive messages “from you”.WhatsApp has been taken over with your number.
- 5Shortly before: a strange call “from the provider” or “the bank” asking for your details.The preparation.
A real example, taken apart
- You did not request a new SIM card.
- From now on all SMS codes go to the new card.
- Every minute counts: bank, e-mail and WhatsApp are now reachable for the scammer.
What you do
- Call your provider — from another phone.Ask to reverse the SIM swap and block your number. Providers have an emergency procedure for this.
- Call your bank.Have payments and login blocked until your number is back.
- Secure your e-mail first.Log in to your e-mail from a computer, change the password, and switch on two-step verification through an app (not SMS). All other passwords get reset from e-mail.
- Then: bank, Apple/Google, WhatsApp, social media.Change passwords, log out sessions, re-register WhatsApp as soon as your number is back.
- File a police report and report it.Police and Fraudehelpdesk. Ask your provider for a log of the change.
Never do this
- Use SMS codes as the only second step for your e-mail or bank when an app code or security key is possible.
- Give your customer number, date of birth or last four digits of your account to someone calling “from the provider”.
- Wait to see whether the signal “comes back by itself”.
Questions people ask
How do I prevent SIM swap?
Two things: a SIM swap block or extra password with your provider (most Dutch providers offer this; ask), and two-step verification through an authenticator app or security key instead of SMS — at least for your e-mail and your bank.
Can an eSIM be taken over too?
Yes, in the same way: by convincing your provider. The protection is the same: a block or extra password on your account with the provider.
My provider says the swap was done “according to procedure”. Who is liable?
That depends on what the provider checked. Request the log, file a police report, and complain to the provider; for losses through your bank, the bank’s goodwill scheme applies.
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