Can I Use my Sprint iPhone 4s with Straight Talk Wireless?

A reader, FatherFisher, asks

I have just upgraded to an iPhone 5S with Sprint. I want to give my old 4S to my son, who is on StraightTalk. When I check the IMEI on their website, they only accept ATT and TMobile 4S phones (or unlocked ones).
So I asked Sprint if they could unlock my phone. After being told the International Dept. does the unlock, they then told me it’s only for use outside the USA. Since my account is in good standing, they did give me the MSL (Master Security Lock??) code, but told me they have no idea how or where to use it.

Is there any way for me to get a CDMA Sprint 4S over to Straight Talk. I have spoken to them and they seem to have no idea — they just want me to buy the CDMA kit and give it a try, which I’d rather not do. OR is there any way to unlock the phone, now that I have the MSL code?


Hi FatherFisher,

This can get a little complicated.  Your Sprint iPhone 4s is both a Sprint CDMA phone and a SIM locked GSM phone. Let me try to explain.

Your Sprint iPhone 4s may be eligible to use on Straight Talk’s sprint compatible network.  Look up the MEID in your iPhone’s settings. Check Settings-General->About. Go to the Straight Talk CMDA BYOP page and enter your zip code and MEID and see if the phone is eligible.

If the phone is eligible, you can register and activate it. You’ll need to buy a Network Access Code at that point. Your son would want to add the phone to his Straight Talk account and transfer his service to it.

The web site should tell you if the phone isn’t eligible. Unfortunately, there isn’t a list of what makes a phone eligible. They might not use the Sprint network in your zip code. They may not want to register your model phone. Rumor is they aren’t allowed to activate Verizon and Sprint iPhone 5 models at this time.  They may be also checking the MEID of your specific phone to see if it is bad, meaning they won’t register it. Bad usually means reported lost or stolen.

Your iPhone 4s also has a SIM slot. But you can’t use it on Straight Talk without an 3rd Party unlock. Sprint SIM locks their iPhone 4s phones. They will not unlock them for domestic use.  They will unlock them for international use. This means if you could use the phone overseas but not here in the USA. And that is really too bad, it’s your phone, if you completed your contract, then you should be able to use it on whatever network you like.

If your son is using a Straight Talk phone with a micro SIM, or you can borrow a micro SIM  from someone, you can complete your unlock. The phone should prompt for the MSL. My guess is at that point, it will unlock and display a message that you can’t use the domestic SIM.

Finally, there are these 3rd party unlocks that can be used to trick the phone into using a SIM. Some readers told me they use the.  Search eBay or Google for sprint iPhone 4s unlock or sprint GPP and you can find more information. While these work, they have limitations. You can’t also update to the latest version of iOS.  These unlocks need to be tested and updated for new versions of iOS. And they cost another $10 – $20 dollars.

If you really can’t use this phone with Straight Talk, I’d sell it and buy a used ATT or Verizon iPhone 4s that you can use. You might be able to break even on the deal or it costs you a few bucks out of pocket. You don’t then need to live with the limitations of the unlock.

Let me know if you have more questions or how you make out. You might also wan to figure out if your son is currently using Straight Talk’s att, tmobile,verizon or sprint network. If it working well for him. He may want to stay on the network.




  1. Josh | | Reply

    Hey, I recently bought an iPhone 4s from sprint, CDMA plus the Sim slot. I just bought the activation kit from Walmart. It did take awhile for me to get working, but its odd because I didn’t have to enter the network access code, for CDMA, and I didn’t have to put in the straight talk sim. So I’m still unsure how it worked. I had to leave my old sprint sim in phone, used the imei from the phone as serial number during activation. After an hr of swapping sims, comparing directions. Lastly I put original sim in phone, rebooted, and walah, it still shows sprint as carrier and only getting 3G. Can I adjust apn to get 4g lte? I’m still a little confused how it worked without network access code or sim from the kit

    • Bob Thompson | | Reply

      Your 4s should only work with Straight Talk’s Sprint network, or possibly the Verizon network. Your phone doesn’t need a SIM nor would it work with any of Straight Talk’s SIM cards. The SIM that comes in the phone, is so that the Sprint phone can roam to other networks when away from the Sprint network. Not sure why you didn’t need to enter the network access code. When you log into your Straight Talk account, does it show your phone as active? You can set the APN on this phone, its done automatically. And finally the iPhone 4s does not support 4G LTE, so there is nothing you can do to get LTE.

  2. Ashley | | Reply

    Hello! I have a sprint iphone 4s I want to switch to straight talk. When I checked it said the phone was compatible! however, when I go to register it I put in my zipcode and it says there is no coverage for that zip code. I have tried multiple zip codes (even my sisters who has a straight talk phone that runs off the sprint towers and still no luck! is there a zip code I could use?

    • Bob Thompson | | Reply

      Hi Ashely,
      I think you best bet is to call straight talk and do the activation. sometimes their web site reports no coverage when their is. Let me know how it goes.

      • Ashley | | Reply

        I did call them and they said the same thing. They said the phone is compatible but there was no coverage in my zip code. I even gave them a different zip code to use and still no luck.

        • Bob Thompson | | Reply

          Hi Ashley,
          Try 66212 the Zip code for Overland Park, KS. That is the city with sprint’s headquarters.

  3. Serena | | Reply

    Hi! I am thinking about buying a used iphone 4s off of craigslist that was used on Sprint but the contract is up and they have it all paid off. So, couldn’t I ues straight talk for this iphone? plesae let me know before I buy it. So please, any input? I was going to buy one on tuesday this coming week. Thanks, -Serena

    • Bob Thompson | | Reply

      Hi Serena,
      This should work. Before you buy, ask the seller for the phone’s MEID and then check it on the Straight Talk website to see if you can activate it. The article has both the instructions to find the MEID and the link to the Straight Talk website.


  4. Gretchen | | Reply

    Hi there – great niche site!

    I’m looking for some help. I have an iPhone 4S from Sprint that is not unlocked, but is no longer in service. I went to Straight Talk and completed the request to enable this phone for service, then completed the request to transfer my existing Straight Talk service (a micro SIM in an old AT&T iPhone4). It has been almost 5 hours since then. Am I doing something wrong? Did I miss a step?

    • Bob Thompson | | Reply

      Hi Gretchen,
      Is the iPhone 4 still active? If not, doing a Reset All Settings on the the 4s and then follow the activation instructions on the 4s. You should need to dial
      ##72786# or ##873238# complete the activation of the phone.

      If the iPhone 4 is still active, contact Straight Talk and open a support ticket to find out the status of the transfer. I would think it would have been faster.


      • Gretchen | | Reply

        Hi Bob! Thanks for the quick response.

        The iPhone 4 is still active, so I will follow up with Straight Talk. I just wanted to make sure that I didn’t miss a step. I will let you know how this goes! 🙂

  5. Phyllis | | Reply

    I have an IPhone 4s. My contract with verizon isn’t up until march 2015. I would like to change to straight talk with no contracts. I don’t see any space that opens to replace a sims card Do they have someone in walmart who has straight talk available to change this over or is this not possible? I don’t know how to do this.

    • Bob Thompson | | Reply

      Hi Phyllis,

      You won’t need a SIM card to use your iPhone 4s with Straight Talk. Your only option will be to use it with Straight Talk’s Verizon network. Straight Talk uses SIM cards for their att and tmobile networks, but your Verizon iPhone 4s in not compatible with them.

      You might get lucky and find someone at a Walmart that can help you but don’t count on it. When you Bring Your Own Phone, you have to do it yourself. Some people find the process easy, others really hard. Either way, you should plan the switch carefully as you may be without phone service during the switch.

      In your case, you would need to.
      Go to the Straight Talk website, and enter your phone’s MEID to see if it can be used on Straight Talk in your area. If so, you’ll need to pay $10 for a network activation code. You can then sign up for Straight Talk and transfer your number from Verizon to Straight Talk. After that you wait, the Verizon service on your phone should be canceled, and it should be activated with Straight Talk.

      You still might save some money if you cancelled you Verizon service and paid the Early Termination Fee. If you have a two year contract ending in March 2015, you hace completed 17 months of your contract. Your ETF would be $350 – (17 * $10) = $180. Thats about $26 a month for the remaining 7 months of your contract. If you were to add that the monthly cost of Straight Talk it would be $45 + 26 = $71 a month. So if your Verizon bill is more than $71 a month it would be cheaper to switch now.

      Try calling Verizon and ask them how much your ETF would be as you are thinking of switching to another phone company. If they ask which service you want to switch to, just tell them you haven’t decided. Ask if you cancel your service if the ETF would be added to your final bill.

      They might offer you a discount to stay. They might offer you a loyalty discount. Just don’t agree to extend your contract.

      Also all this assumes you really want to switch to Straight Talk. You should first figure out how much talk, text, and data you really use per month. If you don’t use so much, you might want to switch to plan that is less than $45 a month.

      Oh, and it doesn’t really matter but if your iPhone is a 4s the SIM slot should be on the right side of the phone. You should see a tiny hole near the center of the metal band.


      • Phyllis | | Reply

        Thanks for your information so quickly. What is a MEID and how do I find it

        • Bob Thompson | | Reply

          Hi Phyllis,
          on your iPhone Tap Settings->General->About. you should find it on that page.

  6. Kevin | | Reply

    to further muddy the conversation. A new law was just passed saying that a provider can not lock the phone to them only. So likley in six months that GSM sim slot would be unlocked, to be used on TING or other sprint sub contractors.

    • Bob Thompson | | Reply

      Hi Kevin,
      The new law requires the carriers to unlock your phone after your contract is up of you pay your Early Termination Fee. I am glad this law passed.

Leave a Reply

Your email address will not be published. Required fields are marked *