A SIM swap attack lets a hacker transfer your phone number to their device. Once they control your number, they receive all your text messages — including SMS verification codes. This means they can bypass SMS-based two-factor authentication, reset passwords, and take over your bank accounts, email, and social media.
Step 1: The attacker gathers your personal information (name, address, last 4 of SSN) from data breaches, social media, or social engineering. Check if your data is exposed with our Email Breach Checker. Step 2: They call your mobile carrier pretending to be you, claiming they lost their phone and need their number transferred to a new SIM. Step 3: With your number, they trigger password resets via SMS and take over your accounts one by one.
Your phone suddenly loses cellular service (no signal, cannot make calls). You receive unexpected emails about password changes or account access. Your carrier sends a notification about a SIM change you did not request. You cannot log into accounts that use your phone number for verification.
Set a carrier PIN: All major carriers let you set a PIN or passphrase required for account changes. Call your carrier and set one immediately. Stop using SMS for 2FA: Switch to authenticator apps (Google Authenticator, Authy) or hardware security keys. SMS is the weakest form of 2FA. Enable port-out protection: Ask your carrier to add extra verification requirements for number transfers. Limit personal info exposure: The less an attacker knows about you, the harder it is to impersonate you to your carrier.
Contact your carrier immediately — go to a physical store with ID if possible. Change passwords on all critical accounts from a device that does not rely on your phone number. Check bank accounts for unauthorized transactions. File a report with your carrier and local authorities. Enable non-SMS 2FA on all accounts after recovering your number.
Run a full Privacy Checkup to assess your overall security. Check what information your IP address reveals. Test your passwords with our Password Strength Checker and generate strong replacements with our Password Generator. The more layers of security you have beyond SMS, the safer you are from SIM swap attacks.