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Does the CMF Phone 1 support eSIM?
No, the CMF Phone 1 has no eSIM and only works with a physical SIM.
The CMF Phone 1 does not have eSIM. For mobile data abroad you will need a physical (travel) SIM with this device, or roaming from your own provider.
Source: GSMArena
Check your CMF Phone 1 for an eSIM yourself
Dial *#06# on your phone. A 32-digit EID number means your phone has an eSIM. On iPhone check Settings > General > About; on Android check Settings > SIM manager.
Frequently asked questions about the CMF Phone 1
Can I use an eSIM on the CMF Phone 1?
No. The CMF Phone 1 is not eSIM-compatible and only works with a physical SIM. For mobile data abroad you'll need a physical travel SIM with this device.