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Unlock Sprint iPhone 4S to AT&T


Unlock Sprint iPhone 4S to AT&T

I apologize if there are countless posts about this as to I could not find the info I was looking for.


I have a Sprint iPhone 4S that I want to use on AT&T. Apparently it is possible and went ahead and requested a COMPLETE unlock code from sprint (not an international unlock) after AT&T told me that I would have to request an unlock code from Sprint for ME to unlock it.


After some run-around, they gave it to me and told me they're not responsible for anything happening and that not all the features of the phone will be available.


Has anyone unlocked a Sprint iPhone 4S to use on AT&T?

If so, what features are apparently unavailable if I do unlock my device?

How do I even use the code they gave me to unlock? They never gave me any info on that or anything. (I also never asked Smiley LOL)


Thanks for any help!

Tags (4)
Message 1 of 19

Re: Unlock Sprint iPhone 4S to AT&T

An unlocked sprint iPhone 4s won't be able to run on att's network. Two different types of networks.
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Message 2 of 19
ACE - Expert

Re: Unlock Sprint iPhone 4S to AT&T

I don't believe that is accurate. The Sprint 4s, I believe, has both CDMA and GSM capability. It is the GSM side that can be unlocked and should work on ATT's network. I know other users have successfully used Verizon's 4s on ATT and technically, I think the Verizon and Sprint models are the same.
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*The views and opinions expressed on this forum are purely my own. Any product claim, statistic, quote, or other representation about a product or service should be verified with the manufacturer, provider, or party.
Message 3 of 19

Re: Unlock Sprint iPhone 4S to AT&T

"Sprint may be able to unlock the CDMA/voice functionality of the device but unable to unlock the GSM/UMTS/LTE portion of the device). Even if unlocked, Sprint devices will not necessarily work on another carrier’s network."


Taken from: http://www.sprint.com/legal/unlocking_policy.html


It seems like their SIM unlocking only applies to travellers planning to use international SIMs. This leaves out local SIM card use on their service. Correct me if I'm wrong.

Message 4 of 19

Re: Unlock Sprint iPhone 4S to AT&T

I would assume they are both same. Theres really only two options in iPhones. The iPhone 4S does have both GSM and CDMA since it's considered a "world phone".


I've read around about people trying to unlock a 4S for use on ATT from Sprint and it seems to me that Sprint is the problem from what I've read.


According to my mother, I'm not sure how accurate it is, but it wasn't until March that Sprint had to legally provide you with the "MSL"(unlocking code) if you asked for it. It was given to me, but it is like what CHOSENLEGACY said; Sprint is not straight foreward at all with their information unlocking of devices for use on other networks outside of international.


I still do believe it would be possible to unlock for use on ATT if its true what SANDBLASTER said about Verizon iPhone 4S' being unocked for use on ATT's network. It can't be legal that Sprint is the only company that doesn't legally "give"(im sure theres a better word) after completing longer than what your contract is for and never late on payments, etc; a good standing customer.


Thanks for the input. But I would need a more definitive answer.

Message 5 of 19

Re: Unlock Sprint iPhone 4S to AT&T

Try calling Sprint and specifically ask them if you can use your unlocked phone on the AT&T network. I looked all over the internet for a specific answer to this and it all goes back to Sprint not allowing it unless you plan on traveling to another country. While the iPhone 4S is compatible with both CDMA and GSM, for some reason Sprint won't "allow" people to change to a domestic network.

Message 6 of 19

Re: Unlock Sprint iPhone 4S to AT&T

I contacted Sprint 3 times and spoke with 3 different representatives and got 3 different answers.


1. I can't use a the iPhone on a GSM network because its a CDMA phone. (unless international of course)

2. The iPhone doesn't have the unlocking feature in general (even for use on another CDMA network)

3. The iPhone can be unlocked but only for CDMA networks. And thats if the phone follows the networks policy and can accept the network's towers. (he "couldn't" answer if my Sprint iPhone 4S could work on Verizon's network)


So it looks like I'm getting no where with unlocking my device for ATT. My next plan is to see if I can contact Verizon to see if I can unlock a Verizon iPhone 4S to use on ATT(or any carrier for that matter) just out of curiosity.



Message 7 of 19

Re: Unlock Sprint iPhone 4S to AT&T

Hi @iZarza 


The Sprint iPhone 4S (along with the Verizon iPhone 4S) does have a GSM side to the device that is used for International Roaming. 


The GSM side of the device is locked by the service provider to block it from using domestic GSM networks (such as AT&T or T-Mobile) at the firmware level and can't be unlocked. Almost all of Sprint's and Verizon phones are locked in this manner to prevent you from using them on another network. 


In my experience I have not seen anyone be sucessful with either Verizon or Sprint get the GSM part of their device unlocked and working properly on AT&T. It couldn't hurt to contact Verizon and see if they have ability to unlock an iPhone 4S and the GSM side of the device. 

Keep in mind that the Verizon iPhone 5, 5C and 5S GSM raidos are unlocked from the factory and will work without any additional unlocking steps. The Sprint 5, 5C and 5S are all locked and need to be unlocked. 


Hope this helps!



Message 8 of 19
Not applicable

Re: Unlock Sprint iPhone 4S to AT&T

@iZarza wrote:


So it looks like I'm getting no where with unlocking my device for ATT. My next plan is to see if I can contact Verizon to see if I can unlock a Verizon iPhone 4S to use on ATT(or any carrier for that matter) just out of curiosity.



Instead of going to Verizon for a phone why not simply purchase an unlocked iPhone from Apple directly or go to your local AT&T store or reseller and buy an AT&T iPhone?

Message 9 of 19

Re: Unlock Sprint iPhone 4S to AT&T

Sprint's official position on unlocking phones:  "Please note that unlocking the SIM slot does not allow for use with domestic (U.S.) SIMs."


Message 10 of 19
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