Library · Crypto, word by word · Scams and security
What is a SIM swap?
A SIM swap is when a criminal gets your mobile carrier to move your phone number to a SIM card they hold, by impersonating you, bribing an employee or hacking the carrier. They then receive your calls and texts, including login codes sent by text message.
What it means for you
If an exchange account or email can be reset with a text-message code, a SIM swap can hand that account to someone else. An app-based authenticator or hardware security key does not depend on your phone number. Losing phone service without warning is a sign to contact your carrier and your exchange at once.
How it works
The FBI lists three routes: impersonating you to the carrier, paying a carrier employee to switch the number, or phishing carrier staff with malware to reach the carrier's systems. Once the number moves, your calls and texts go to the criminal's phone. They request password resets, receive the text-message codes, and take over email and then exchange accounts. Social media posts about owning crypto can make someone a target. Authenticator apps, physical security keys and biometrics do not rely on the phone number, so a swapped SIM does not hand them over.
Source: FBI IC3: Criminals increasing SIM swap schemes to steal millions (PSA220208) · checked 4 October 2026
On Cryptominium
Related words
Educational content, not financial advice. Written by hand and checked against the source named above. Something wrong? Tell us and we reply within two business days.