Your Phone Number Is More Dangerous Than Your Social Security Number

That sounds hyperbolic, but consider this: your Social Security number is supposed to be private. Your phone number, on the other hand, is tied to your identity, your location, your bank accounts, your two-factor authentication, and it is almost certainly publicly searchable on dozens of data broker websites right now.

The FBI's Internet Crime Complaint Center (IC3) reported over 2,000 SIM swapping complaints in 2022 alone, with losses exceeding $72 million. And SIM swapping is just one of the threats. Your phone number is a skeleton key that can unlock far more than most people realize.

8 Things Someone Can Do with Your Phone Number

1. SIM Swapping: Hijacking Your Phone Number

SIM swapping (also called SIM jacking) is the most dangerous phone number attack. Here is how it works:

The attacker gathers your personal information (name, address, last four digits of SSN) from data brokers or social engineering
They call your mobile carrier, impersonate you, and claim they need a new SIM card
The carrier transfers your phone number to the attacker's SIM card
Your phone loses service. The attacker now receives all your calls and texts
They use SMS-based two-factor authentication to access your email, bank accounts, and cryptocurrency wallets

Real-world impact: In January 2024, the SEC's official X (Twitter) account was compromised via a SIM swap attack, leading to a fake announcement about Bitcoin ETF approval that briefly moved markets. Individual victims have reported losses of $10,000 to $20 million in cryptocurrency theft via SIM swapping.

2. Two-Factor Authentication Bypass

Most online services offer SMS-based two-factor authentication (2FA). If someone has your phone number and can intercept your texts (via SIM swapping, SS7 attacks, or social engineering your carrier), they can bypass 2FA on:

Email accounts (Gmail, Outlook, Yahoo)
Banking and financial apps
Social media accounts
Cryptocurrency exchanges
Cloud storage services

This is why security experts recommend app-based authenticators (Google Authenticator, Authy) or hardware keys (YubiKey) over SMS-based 2FA.

3. Social Engineering and Pretexting

With your phone number and the personal information data brokers provide alongside it, an attacker can:

Call your bank pretending to be you and pass phone-based identity verification
Contact your employer posing as a family member in an "emergency"
Call your elderly parents claiming to be a grandchild in trouble
Reach out to your contacts from a spoofed number that displays your caller ID

The FCC estimated that Americans received approximately 50 billion robocalls in 2023. Many of these calls use personal information sourced from data brokers to make the scam more convincing.

4. Account Discovery and Takeover

Your phone number is a universal identifier across services. A determined attacker can:

Use password reset flows on websites that accept phone-based recovery to discover which services you use
Cross-reference leaked databases where your phone number appears alongside other credentials
Search social media platforms where your phone number is linked to your account (WhatsApp, Telegram, Signal all use phone numbers as identifiers)

5. Location Tracking

Your phone number can reveal your physical location through several mechanisms:

SS7 vulnerabilities: The Signaling System 7 protocol that connects cell networks worldwide has known vulnerabilities that allow tracking a phone's location to within a few hundred meters. While exploiting SS7 requires specialized access, this capability is sold by surveillance companies to governments and, occasionally, to private parties.
Carrier lookup services: Legitimate services used by businesses to identify carrier information can reveal your general geographic area.
Social engineering carriers: An attacker posing as you can request location services or account details from your carrier.
Data broker profiles: People-search sites associate phone numbers with physical addresses, providing a current or recent home location.

6. Spam Calls, Robocalls, and Phone Scams

Once your phone number enters the data broker ecosystem, it is sold and resold thousands of times. The result:

Billions of robocalls annually: The FCC receives over 200,000 unwanted call complaints per year, but the actual volume is estimated at 50+ billion calls
Targeted scam calls: Scammers use data broker information to personalize calls, referencing your name, address, or recent activity
Neighbor spoofing: Calls that appear to come from your area code and prefix, making them seem local and trustworthy

7. Harassment and Stalking

A phone number is one of the most sought-after pieces of information for stalkers and harassers:

Direct contact: Unwanted calls and threatening text messages
Doxxing: Publishing your phone number alongside your name and address online
Swatting: Making false emergency reports tied to the phone number's registered address
Signing up for unwanted services: Subscribing your number to spam services, religious organizations, or controversial political groups

8. Identity Verification Exploitation

Many services use phone numbers for identity verification. An attacker with your number can:

Port your number to a new carrier (a form of SIM swapping)
Verify new accounts using your number during the window between SIM swap and detection
Access voicemail (many carriers use the last four digits of your phone number as the default PIN)
Exploit "verify via call" systems that read a code aloud to the person who answers

How Your Phone Number Becomes Public

Most people do not realize how widely their phone number is distributed:

Data Brokers

This is the primary distribution channel. Data brokers collect phone numbers from:

Public records (property records, voter registration, court filings)
Commercial databases (loyalty programs, warranty registrations, online purchases)
App permissions (apps that request access to your contacts upload entire address books)
Telecom records (carrier data sold to aggregators)
Social media (phone numbers added for security or contact purposes)

A single phone number typically appears on 20-50 data broker sites. Each of these sites is publicly searchable, meaning anyone who knows your name can find your phone number, and anyone who has your phone number can find your name and address.

Data Breaches

Phone numbers are included in most data breaches. When a company's database is breached, the stolen data typically includes names, emails, phone numbers, and addresses. This data ends up on dark web marketplaces within days.

Your Own Actions

You unknowingly share your phone number more than you think:

Business cards and email signatures
Online forms and registrations
Social media profiles
Contest entries and warranty cards
Real estate transactions
Court filings and legal proceedings

How to Make Your Phone Number Unsearchable

Step 1: Remove Your Number from Data Brokers

This is the single most impactful step. As long as your phone number is listed on data broker sites, it is publicly searchable and will be sold to new buyers continuously.

Manual approach: Search for your phone number on sites like Spokeo, BeenVerified, Whitepages, TruePeopleSearch, FastPeopleSearch, and others. Submit individual opt-out requests to each site. Repeat every 3-6 months as your information gets re-listed.

Automated approach: GhostMyData scans 1,500+ data broker sources for your phone number and submits removal requests automatically, with continuous monitoring for re-listings. Start with a free scan to see where your number currently appears.

Step 2: Protect Your Carrier Account

Set a carrier PIN or passcode: Call your carrier (AT&T, T-Mobile, Verizon, etc.) and set up a port-out PIN. This prevents SIM swapping without the PIN.
AT&T: Use the myAT&T app or call 611 to set up a passcode
T-Mobile: Enable "Account Takeover Protection" in your account settings
Verizon: Set up a "Number Lock" in the My Verizon app
Enable SIM lock: Some carriers offer the ability to lock your SIM card, preventing it from being transferred

Step 3: Switch to App-Based 2FA

Replace SMS-based 2FA with app-based authentication wherever possible:

Google Authenticator or Microsoft Authenticator for most services
Authy for cloud-backed codes across devices
Hardware security keys (YubiKey, Google Titan) for highest security
Update 2FA on your email, banking, social media, and cryptocurrency accounts first

Step 4: Use a Secondary Number

Consider using a VoIP or secondary number for public-facing activities:

Google Voice: Free, provides a separate number for online forms and businesses
Burner apps: Disposable numbers for Craigslist, dating apps, and temporary uses
Business line: Keep your personal number off business cards and websites

Step 5: Register with the Do Not Call Registry

Visit DoNotCall.gov to register your number. While this does not stop scammers (who ignore the registry), it does reduce legitimate telemarketing calls. Registration is free and does not expire.

Step 6: Audit and Minimize Exposure

Remove your phone number from social media profiles
Do not use your primary phone number for online shopping accounts
Never enter your real phone number on sweepstakes, quizzes, or "free offer" forms
Check app permissions and revoke contact access for apps that do not need it

What to Do If Your Number Is Already Compromised

If You Suspect a SIM Swap

Contact your carrier immediately (from a different phone) and report the unauthorized port
Change passwords on all critical accounts (email first, then banking, then social media)
Check financial accounts for unauthorized transactions
File a report with the FBI's IC3 at ic3.gov
Freeze your credit at all three bureaus
Contact your bank and flag your accounts for potential fraud

If You Are Receiving Threatening Calls

Document everything: Save voicemails, screenshot text messages, note call times and numbers
Report to police: Especially if threats include violence, stalking, or extortion
Report to the FCC: File a complaint at fcc.gov/consumers/guides/report-unwanted-calls
Block the numbers: Use your phone's built-in blocking features
Consider changing your number: As a last resort, get a new number and be careful about where you share it

Frequently Asked Questions

Can someone hack my bank account with just my phone number?

Not with the phone number alone, but it is a critical piece of the puzzle. Combined with other personal information (which is readily available from data brokers), an attacker can use your phone number for SIM swapping, which then provides access to SMS-based two-factor authentication codes for your bank.

Should I change my phone number if it is on data broker sites?

Changing your number is a last resort because it creates significant inconvenience. A more practical approach is to remove your current number from data broker sites using an automated service, set up carrier protections (port-out PIN, account takeover protection), and use a secondary number for public-facing activities going forward.

How do I find out which data broker sites have my phone number?

You can search for your phone number manually on major people-search sites like Spokeo, Whitepages, and BeenVerified. However, this only covers a fraction of the data brokers that may have your information. A free GhostMyData scan checks 1,500+ data sources simultaneously.

Is the Do Not Call Registry effective against scammers?

No. The National Do Not Call Registry reduces legitimate telemarketing calls, but scammers and robocallers ignore it entirely. The registry has no mechanism to prevent or penalize illegal callers, particularly those operating from overseas. Removing your number from data brokers is more effective because it cuts off the supply of numbers that scammers purchase.

Can someone track my location with just my phone number?

In theory, yes. SS7 protocol vulnerabilities allow location tracking of any phone number, and this capability is sold by surveillance companies. In practice, this type of tracking requires specialized access and is primarily used by law enforcement and intelligence agencies. However, data broker profiles that associate your phone number with your home address provide a simpler form of location information to anyone who searches.

What is the best way to protect my phone number going forward?

The most effective combination is: (1) remove your number from data broker sites, (2) set up a port-out PIN with your carrier, (3) switch to app-based 2FA instead of SMS, (4) use a secondary number for non-essential services, and (5) maintain ongoing monitoring for re-listing on data broker sites.

What Can Someone Do with Your Phone Number? More Than You Think