Pusaram

SIM swap and account takeover

A fraudster gets your phone number moved to their SIM, or logs in as you, and uses it to reset passwords and approve payments.

How it works

  • The fraudster gathers details about you from leaks, phishing or social media, then contacts your mobile operator pretending to be you and asks for a replacement SIM.
  • Once your number is theirs, one-time codes and password resets go to them. Your own phone suddenly loses signal.
  • They can then reset email and banking passwords and move money, often within minutes.

Warning signs

  • Your phone suddenly shows 'no service' or 'emergency calls only' for no clear reason.
  • Messages about a SIM change or a new device login that you did not request.
  • Unexpected password-reset emails or one-time codes.
  • Calls asking you to confirm details or press a key to 'upgrade your SIM'.

What to do

  • If service drops unexpectedly, contact your operator from another phone straight away and your bank at the same time.
  • Use an authenticator app instead of text messages for important accounts where possible, and set a strong separate email password.
  • Never share the codes that arrive by text. Be careful what personal details you post publicly.

A made-up example of what you might hear

'Sir, your SIM is expiring today. To keep your number active, reply YES to the message and share the code that you receive.'

If you already paid or shared a code

  • Call your bank or card issuer straight away and ask them to block the card, account or payment. Use the number on the card or the official website.
  • Change passwords for any account that may be affected, starting with email and banking. Turn on two-step verification.
  • Report it to the authorities (see the list below). Keep screenshots, phone numbers, account details, transaction IDs and times.

Where to report

Author and editorial reviewer: Prashant Nandkishor Maheshwari, 2026-10-18. Education only. Rules and reporting channels differ by country.