SIM Swap Scams: How They Work and How to Protect Your Phone Number

When your phone suddenly shows "No Service", you may think you're just in a dead zone. But then you can't log into your bank app, and you're getting emails about unusual login activity. Someone has hijacked your phone number and is now using it to intercept your texts and 2FA codes.

In a situation like this, every minute counts to protect your identity and financial accounts. Detecting the problem early can limit the damage.

In this guide, I’ll walk through how SIM swap scams work and how to use tools like identity theft protection services to better safeguard your accounts.

What is a SIM swap scam?

A SIM (Subscriber Identity Module) swap scam happens when someone tricks your mobile carrier into transferring your phone number to their SIM card.

Once they control your number, they can receive all your texts and calls, including two-factor authentication (2FA) codes. Intercepting 2FA codes makes it much easier to access your bank account, crypto wallet, or email.

Also known as SIM swapping, SIM swap fraud, or SIM hijacking, this is a form of account takeover fraud. It's dangerous because your phone number is often linked to sensitive accounts.

How does a SIM swap scam work?

A SIM swap scam is difficult to pull off. Scammers take multiple intense steps to successfully impersonate you and manipulate your mobile carrier.

But the payoff is worth it for scammers.

The FBI's 2025 IC3 Report logged 971 SIM swap complaints and nearly $17.4 million in losses. While this is lower than in previous years, it shows that SIM swapping is still having an impact.

Here's how a SIM swap scam works:

1. Learning about you: Scammers need your personal information to impersonate you. They want personally identifiable information such as your birthday, address, or Social Security number. There are a few ways they can collect this information. They can look you up on social media or use social engineering tactics. They could find your information through data breach assets for sale on the dark web. Or they may send you a phishing email and trick you into giving them key details.
2. Impersonation: The scammer pretends that they're you. They contact your mobile carrier to report that your phone was lost and request help moving your phone number to a new SIM or eSIM.
3. SIM swap: Your number gets transferred to a different SIM or eSIM card. The scammer gains control of your number, and your phone service will stop working.
4. Account takeover: You've set up your phone number to verify your identity. In the hands of scammers, that number lets them receive 2FA codes or calls. They can click "Forgot password" on a site to attempt to gain access. When they enter those codes, companies allow password changes and let scammers into the account.
5. Financial loss: Scammers will drain your bank accounts and crypto wallets. They may also access your email accounts to steal personal data and further identity theft attempts.

SIM swap fraud doesn't involve stealing your phone. Instead, scammers go after the weak link between phone-based 2FA and your mobile carrier's verification process. By hijacking your phone number, they can get direct access to your accounts.

Warning signs you've been SIM swapped

According to our survey, 42% of identity theft victims first realized something was wrong when they discovered missing funds or unusual charges on their account.

At that stage, financial fraud has already occurred, and acting fast is even more important. Fast reactions are essential in protecting yourself from scammers. The sooner you respond, the more you can minimize damage.

Here are 6 signs of an attempted or successful SIM swap:

1. Your carrier sends security alerts asking you to confirm or deny access.
2. You receive a notification that your SIM or number was transferred.
3. Your phone suddenly loses service.
4. You see unusual login activity on your online accounts.
5. You notice unfamiliar charges or withdrawals.
6. Your apps stop working on your phone.

How to protect yourself from a SIM swap scam

In 2023, the Federal Communications Commission (FCC) created baseline rules to protect against SIM swapping. It requires mobile carriers to immediately notify a person when a SIM change request is made. Providers must also ensure they authenticate a person's identity before transferring phone numbers.

The FCC rules have helped reduce SIM swapping, but it's still possible. Let's look at a few tasks you can do to protect yourself:

• Lock account: Mobile providers usually offer a free option to lock or freeze SIM cards, making them impossible to transfer.
• Set unique passwords: 2FA is just one part of gaining access to your account. A strong, unique password for each account makes it harder for scammers to gain access. A password manager can help keep track of all your login credentials.
• Don't respond to unsolicited messages: Phone providers will never ask for personal information, such as your password or payment information.
• Don't share personal information online: Keep your private data secure by not sharing your cell phone number, personal details on social media, or your financial assets.
• Switch to different 2FA methods: Instead of text or calls to receive 2FA codes, consider using passwordless authentication, like authentication apps or biometrics. These are harder for a scammer to intercept.
• Sign up for identity theft monitoring and protection: According to our survey, 71% of victims who were subscribed to an identity theft monitoring service were alerted to the theft by that service. Early alerts can help you minimize losses and take back control of your identity.

Bottom line

A SIM swap scam hijacks your phone number and transfers it to a SIM card that the scammer possesses. A few simple steps can make a big difference in preventing SIM swapping.

Start by locking your SIM card on your account. It makes it impossible for a phone carrier to transfer your phone number. Unique passwords, authentication apps, or biometrics are all helpful at protecting your accounts without relying on phone service.

You should also consider signing up for a secure identity theft protection service that monitors the dark web, bank accounts, credit reports, and more to help keep your identity secure.

Learn about the best identity theft protection services we’ve vetted.

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