eSIM
An eSIM is a digital SIM card built into a device: the operator profile is loaded remotely without a plastic card, and one device can hold several numbers.
What it is
It is the same SIM card, only without the plastic. The chip is already inside the phone, and the number is “installed” with a QR code or through the operator’s app. One device can hold several profiles and switch between them.
How it differs from a virtual number
An eSIM is a real mobile number from a telecom operator. For messengers it looks like an ordinary number on a SIM card, not like an internet number. That is why registration usually raises fewer questions.
How it looks in practice
It is convenient for a company: numbers can be issued to employees remotely, without sending cards. A new phone means moving the profile. Several work numbers on one device are possible without a second slot.
Why it matters
The main question is who the number is registered to. If an eSIM is registered to an employee, the number leaves with them at dismissal, together with access to the messenger. A work number should be under the company’s contract with the operator.
The second question is recovery. Deleting an eSIM from a phone is easy, getting it back is harder: a new profile from the operator is needed, sometimes with an identity check. If the phone is lost and the recovery procedure is unclear, the work number can drop out for days.
The typical mistake
Treating an eSIM as invulnerable. Number takeover is possible here too: an attacker persuades the operator to reissue the profile to their own device. The protection is the same as for ordinary numbers: two-factor authentication in messengers and a separate password for number operations at the operator.
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