A SIM without the plastic card
An eSIM is a digital SIM profile downloaded to a compatible phone. It can provide mobile data while your primary SIM remains available for calls or verification messages.
Compatibility has two parts
The phone must support eSIM and be carrier-unlocked. A model can include eSIM hardware and still reject a travel plan when the original carrier lock remains active.
Installation is not always activation
Scanning a QR code usually installs the profile. Validity may start at installation, purchase, or first network connection, so check the plan rule before scanning.
Use dual SIM deliberately
Keep the travel eSIM selected for mobile data, turn off data switching, and disable data roaming on the primary SIM unless your carrier confirms it is safe.