Advanced conversation on SIM cards


‘Reusing’ SIM Cards

For others who do see the topic and are looking for information there are a number of other things to consider.

  1. Is the current phone activated on the GSM or CDMA network?
  2. If the current phone is activated on CDMA, is a SIM or a ISIM installed?
  3. If the CDMA network is desired does the new phone need a CDMA SIM or a ISIM?

CDMA network activation and SIM requirements:
At this time it is not possible to move a used (or install new) CDMA SIM or ISIM from a activated phone to a phone that has not been previously activated using RW’s GSM or CDMA network.
Compatible phones will require either a CDMA SIM or ISIM depending upon phone model.

How do we identify a ISIM?

'Reusing' SIM Cards

a bit if info


Easy enough to determine. Power down the phone, than remove and examine the SIM. If the public part of the word Republic is green, it’s GSM. Otherwise, it’s CDMA.

An ISIM is a SIM. It’s a type of CDMA SIM.

Not terribly important since any type of CDMA SIM may only be obtained from Republic support and they will know which one to send based on phone model.

Bottom line (for good reasons), Republic’s preferred process when activating a new phone is to use a new SIM. Any phone purchased from Republic’s online store will come with an appropriate SIM. All bring your own phones must first be activated on GSM.

Generally, it’s possible to move an active GSM SIM from one phone to another phone. GSM technology was designed with this in mind.

Historically, it hasn’t been possible to move an active CDMA SIM (of any type) between phones. CDMA technology was not designed to accommodate doing so, though there have been attempts (with varying degrees of success) to make CDMA SIMs behave more like GSM SIMs for this purpose. Further, it is not currently possible to move an active CDMA SIM (of any type) between Republic phones. Such a swap (if it worked at all) would first require activating the target Republic phone on GSM. After doing so, one might attempt reactivating a CDMA SIM in the new phone. If it works (in my estimation at best a 50-50 shot) great. If not, one will need to request a new CDMA SIM from support. Again, based on phone model, they would know which CDMA SIM to send.


way is to know all newer phones that can activate on CDMA (Since the Moto E4) will need or have an iSIM all phones before this will have the older SIM


It may be very important to those have have several RW phones and would like to reuse an existing CDMA SIM and one reason for the question of how to identify the difference visually. The information is not available in a Help Document yet.

Correct. I have moved one successfully and believe it needed to be deactivated prior to reusing. In my case it was deactivated by activating the donor phone on the GSM network.


I was thinking they may be able to be differentiated by the first several numbers of the SIM’s ICCID if Sprint has a identifier number unique to the ISIMs or RW would use a different color of printing to avoid confusion in our future? FYI, other US carriers do apparently use different ident #s depending upon?


Those numbers are used now on the republic wireless sim to tell the difference between gsm and cdma sims Is My Republic Wireless SIM Card CDMA or GSM? – Republic Help but I haven’t seen anything about a difference for isim identification yet.


If the 19 to 20 digit number also known as the ICCID on the SIM card starts with 89011, it is CDMA. If the ICCID begins with 89012, it is a GSM SIM card.

All cell phone SIM ICCIDs should begin with 89, 01 is the US country code. The next three #s identify the carrier. Sprint’s carrier indent is 120. One of T-Mobile’s indents is 260.