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    SIM Swap Attacks: How Criminals Hijack Your Phone Number

    Last updated: March 2026

    sim swap scam
    sim swapping
    phone number hijack
    sim card fraud

    Overview

    SIM swap attacks occur when criminals convince your mobile carrier to transfer your phone number to a SIM card they control. Once they have your number, they can receive your text messages and calls, including two-factor authentication codes. This gives them access to your bank accounts, email, social media, and cryptocurrency wallets. SIM swapping has become one of the fastest-growing forms of fraud, with losses reaching hundreds of millions of dollars.

    How This Scam Works

    1

    Criminals gather personal information about the victim through social media, data breaches, phishing, or social engineering.

    2

    They contact the victim's mobile carrier pretending to be the account holder, claiming a lost or damaged phone and requesting a SIM transfer.

    3

    Once the carrier transfers the number, the criminal's phone receives all calls and texts meant for the victim.

    4

    With access to SMS-based two-factor authentication codes, the criminal quickly accesses and drains bank accounts, cryptocurrency wallets, and other valuable accounts.

    Warning Signs

    Sudden loss of cell phone service (no signal, calls, or texts)
    Notification from your carrier about a SIM change you did not request
    Unable to log into your accounts despite using correct passwords
    Unexpected password reset notifications
    Unusual activity on your bank or financial accounts
    Social media accounts posting content you did not create

    Real Scam Examples

    These are examples of messages used in this type of scam.

    Carrier Notification

    Your SIM card has been changed. If you did not request this change, please contact customer service immediately at [carrier number].

    Phishing Text (used to gather info)

    Your mobile account requires verification. Reply with your account PIN and the last 4 digits of your SSN to avoid service interruption.

    How to Protect Yourself

    1Set up a PIN or passphrase with your carrier

    Add an extra security PIN or passphrase to your mobile account that must be provided before any changes can be made, including SIM swaps.

    2Use authenticator apps instead of SMS

    Replace SMS-based two-factor authentication with authenticator apps like Google Authenticator, Authy, or hardware security keys whenever possible.

    3Limit personal information shared online

    Reduce the personal details you share on social media. Criminals use publicly available information to impersonate you to your carrier.

    4Contact your carrier about SIM lock features

    Many carriers offer SIM lock or number lock features that prevent unauthorized transfers. Enable these protections on your account.

    5Act immediately if you lose service

    If your phone suddenly loses service, contact your carrier right away. Quick action can prevent criminals from accessing your accounts.

    Frequently Asked Questions

    Think you have received a scam like this?

    Paste the suspicious message into our free AI-powered scam analyzer.

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