What is SIM swapping and why does it matter for crypto?
A SIM swap moves your phone number to a criminal's SIM, and crypto exchanges that use SMS codes can be exposed. Warning signs and protections matter.
Vahe HakobyanEditor-in-chief
Updated Oct 5, 20263 min readFact-checked
On this page
Your phone number often acts as a key to online accounts. In crypto, that link can be risky because account access can happen quickly and transfers are usually irreversible.
What is a SIM swap?
A SIM swap is a crime where someone gets a new SIM card activated with your phone number. The carrier moves your number to the attacker's SIM, so your phone may lose service while the attacker gets your calls and texts. The phone itself is not hacked.
Why does it matter for crypto?
Many crypto exchanges use SMS codes as a second step when you log in or withdraw. If an attacker controls your number, those codes go to the attacker, who can then reset passwords and approve a withdrawal.
How can you protect your crypto?
Protection starts with reducing what your phone number can unlock. You also need a plan for the first hours after a swap.
How does a SIM swap happen?
Attackers usually gather personal details about you. They may call your carrier and pretend to be you, or they may pay someone inside the carrier to move your number. With your texts, they reset passwords and steal crypto from accounts that use SMS verification.
Frequently asked questions
Your phone may lose service, or calls and texts may stop. Ask your carrier if your number was ported.
No, not by itself. A swap could help only if you stored the seed phrase on the phone or in cloud notes tied to your number.
Yes. The swap happens at the carrier, so your phone does not need to be on. Having it off may only delay when you notice.
No. A swap targets your phone number at the carrier, not the software on your phone. Phone hacking usually involves malware or tricking you into giving up access.
