Tips & Tricks

CDMA Networks

Worldwide, there are two main types of networks:

  1. Global System for Mobile Communication (GSM): AT&T, Vodafone
  2. Code Division Multiple Access (CDMA): Verizon, Sprint, Nextel, Alltel

As their infrastructure is regarded, they are differently built – one is supporting a SIM slot (GSM) but the other not (CDMA).

Global System for Mobile Communication (GSM)

GSM phones can be unlocked and switch carriers, whereas CDMA carriers use network-based white lists to verify their subscribers. That means you can only switch CDMA phones with your carrier’s permission.

In some cases, CDMA phones might have a SIM slot, but they support only foreign GSM network. This means you cannot use a Verizon phone with a GSM network inside the US, but you can use it with a GSM network in another country if you travel abroad.

Indeed, there were set up some mergers between GSM and CDMA companies ( T-mobile and MetroPCS, Sprint and SoftBank ), but the most CDMA devices will not be compatible with GSM networks.

Code Division Multiple Access (CDMA)

CDMA networks are the most common in North America and parts of Asia (CDMA networks examples: Verizon, Sprint, US Cellular, Straight Talk, Unefon). Unlike GSM phones that work with a SIM card inside, the CDMA phones do not work based on a SIM. It is easy to swap phones on GSM networks because you only need to take out your SIM card and put it on a different phone (the new phone will have your number).

cdma-networks

That’s not the case with CDMA, where you can only switch phones with your carrier’s permission, but typically CDMA carriers do not give you permission to switch phones.

Based on this, you have to understand that only GSM phones can be unlocked to switch carriers, whereas CDMA carriers use network-based white lists to verify their subscribers. That means you can only switch CDMA phones with your carrier’s permission.

What really matters is the type of network prior to the merge. If the network infrastructure was CDMA from the very beginning, so it will be after the business merge, because of its initial infrastructure.

Note: we do not unlock CDMA phones. Please do not place an order if your device has a CDMA infrastructure.

CDMA networks:

Provider
Country
Technology
MovicelAngolaCDMA
CoTeCalArgentinaCDMA
SetarNVArubaCDMA
ArgoNETAustriaCDMA
AztrankAzerbaijanCDMA
CATELAzerbaijanCDMA
NakhtelAzerbaijanCDMA
CitycellBangladeshCDMA
RanksTelBangladeshCDMA
Speednet / SMARTBelizeCDMA
Benin TelecomsBeninCDMA
CellularOneBermudaCDMA
Freedom MobileCanadaCDMA
MTSCanadaCDMA
SogetelCanadaCDMA
TBayTelCanadaCDMA
Virgin MobileCanadaCDMA
China TelecomChinaCDMA
O2Czech RepublicCDMA
U:fonCzech RepublicCDMA
Tatem TelecomDemocratic Republic of CongoCDMA
Net 1DenmarkCDMA
EthiotelecomEthiopiaCDMA
MagtiComGeorgiaCDMA
SilknetGeorgiaCDMA
InquamGermanyCDMA
NetCologneGermanyCDMA
Expresso TelecomGhanaCDMA
ClaroGuatemalaCDMA
MovistarGuatemalaCDMA
cslHong KongCDMA
BSNLIndiaCDMA
MTNLIndiaCDMA
MTS IndiaIndiaCDMA
Ping MobileIndiaCDMA
Reliance CommunicationsIndiaCDMA
TATA DOCOMOIndiaCDMA
STI (Ceria)IndonesiaCDMA
SmartfrenIndonesiaCDMA
PelephoneIsraelCDMA
au (KDDI)JapanCDMA
FonexKyrgyzstanCDMA
NExiKyrgyzstanCDMA
SapatcomKyrgyzstanCDMA
TriatelLatviaCDMA
China TelecomMacauCDMA
TelmexMexicoCDMA
InterdnestrcomMoldovaCDMA
UnitéMoldovaCDMA
G-MobileMongoliaCDMA
SkytelMongoliaCDMA
InwiMoroccoCDMA
MPTMyanmarCDMA
KPNNetherlandsCDMA
GiCellNigeriaCDMA
MultilinksNigeriaCDMA
VisafoneNigeriaCDMA
Ice.netNorwayCDMA
Go CDMAPakistanCDMA
PTCL (Vfone)PakistanCDMA
WorldCallPakistanCDMA
Open MobilePuerto RicoCDMA
SprintPuerto RicoCDMA
BaikalWestComRussiaCDMA
ETKRussiaCDMA
Sky LinkRussiaCDMA
Sotel-CCBRussiaCDMA
Volga TelecomRussiaCDMA
TCRNRussiaCDMA
RTCRussiaCDMA
Orion TelekomSerbiaCDMA
SierratelSierra LeoneCDMA
NeotelSouth AfricaCDMA
LG U+South KoreaCDMA
SK TelecomSouth KoreaCDMA
Dialog Broadband NetworksSri LankaCDMA
Lanka BellSri LankaCDMA
Sri Lanka TelecomSri LankaCDMA
TritelSri LankaCDMA
TelesurSurinameCDMA
Net 1SwedenCDMA
Asia Pacific TelecomTaiwanCDMA
SasatelTanzaniaCDMA
TTCLTanzaniaCDMA
ZantelTanzaniaCDMA
I-TelUgandaCDMA
IntertelecomUkraineCDMA
MTSUkraineCDMA
PEOPLEnetUkraineCDMA
Alaska CommunicationsUnited StatesCDMA
Boost MobileUnited StatesCDMA
CellcomUnited StatesCDMA
C Spire WirelessUnited StatesCDMA
FreedomPopUnited StatesCDMA
Nex Tech WirelessUnited StatesCDMA
nTelosUnited StatesCDMA
SprintUnited StatesCDMA
U.S. CellularUnited StatesCDMA
Straight TalkUnited StatesCDMA
VerizonUnited StatesCDMA
Virgin MobileUnited StatesCDMA
UzbektelecomUzbekistanCDMA
MovilnetVenezuelaCDMA
Yemen MobileYemenCDMA
Nepal TelecomNepalCDMA
United Telecom LimitedNepalCDMA
PowertelZimbabweCDMA

12 Comments

  • hello.
    I have an Galaxy S8 locked to US Cellular (CDMA). could it be unlock to work with T-mobile (GSM)

    • Hello Dan, Unfortunately, we don’t provide services for Cellular (CDMA). Our services are working only for GSM providers.

  • Hi I HV LG h735G4 is blocked so I tryed all the way u listed by it’s not responding it’s saying its permanently locked and can not be unlocked ,that’s when I will be on Sim Unlock Process

  • I bought a used Samsung Galaxy with only CDMA which was locked to Verizon and I factory reset it. If the previous owner had a cellphone plan on the phone but switched to a new phone, can I use a cellphone plan on it from the Verizon network without unlocking it? Do I need to go into a Verizon store for them to activate the plan?

  • I have a unlocked s7 edge originally with bell (Canada). I cross quite often to states SO I bought the 55$ unlimited Straight Talk plan from Wal-Mart , came with a At&t, tmobile and Verizon SIM cards. I popped in the Verizon SIM and followed the steps and it finally said Phone is not compatible ?! Is this a gsm cdma issue or what? Any help would be appreciated.

  • my samsung j3 luna pro has both gsm/CDMA functions. but is network locked to CDMA.
    ANY CHANCE OF UNLOCKING IT FOR USE ON A gsm NETWORK?

  • Verizon DOES NOT lock “world devices” such the Samsung note 8,galaxy 8 and 8+ and also the lg v6 or lgv30.
    Simply put in an ATT sim card,power on the phone and your good to go.

    • Hi Tom, indeed some smartphones sold by Verizon are not locked at all. However, older phones manufactured until 2017 support only CDMA networks. For example, an S7 edge from Verizon won’t work (even if unlocked) with an AT&T Sim card.

  • I bought a used Boost HTC A9 phone. She bought it unlocked off of the HSN network with a free 30 days of service. This phone also has a SIM slot and she was able to use an AT&T card. Curious about my options as Sprint and boost don’t work in my area and when I put my old Straight Talk SIM in to check it I got a SIMLock enabled message.

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