I understand that both SIM's need to from a different carrier unless the device is locked then has to be the same carrier. I also see that if SIM is CDMA then the eSIM can not also be CDMA. My question is if both plans are from the same carrier, could they both be CDMA? Or would same carrier only apply with ATT or T-Mobile (GSM)?
iPhone XS, iOS 13
No they cannot both be CDMA (Using Dual SIM with an eSIM - Apple Support). So in the USA if you first set up a Verizon or other CDMA carrier, the second line will have to be from AT&T, T-Mobile or a non- CDMA MVNO.
No they cannot both be CDMA (Using Dual SIM with an eSIM - Apple Support). So in the USA if you first set up a Verizon or other CDMA carrier, the second line will have to be from AT&T, T-Mobile or a non- CDMA MVNO.
Thanks Michael. Forgive the follow up, but I want to make sense of what I’m seeing on apple support. We could have the same carrier on SIM and eSIM if it was AT&T, T-Mobile or non CDMA? Thanks!
Yes. The way CDMA legacy networks register devices in their database for access to their networks is completely different than how GSM legacy systems do. With CDMA, a device’s physical hardware ID cannot have two instances on the network at the same time.
One would hope as true 5G tools out, those legacy network aspects will disappear, but at least for now, Verizon is still using CDMA protocols to connect their users devices to their network.
Dual SIM with an eSIM
