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Can't use SIM card in different phone - why?


Can't use SIM card in different phone - why?

I got fed up with my S5's screen flickering, sometimes taking 100 or more button presses to get to the lock screen, and bought a new Moto G5plus from Amazon.  The S5 uses a micro SIM, the Moto uses a nano sim, but it's easy to trim the excess plastic to the new size, and has been pretty much standard procedure.  Trimmed it, put it in the Moto, and all was well, until I went to the Sprint website to disable the S5 and enable the Moto.  When I entered the SIM card #, it wouldn't let me go any further, saying it was "incompatible or already in use".  Yes, it was in use, on my S5, which I was trying to disable and replace with the Moto.  Phone support also couldn't enable it, and couldn't give me anything but vague reasons.

My understanding of SIM cards is that it just contains user info for the network, so why on earth would the same card not work universally, assuming it's in the slot and connected?  If they've now gone to different cards for every phone, what on earth is the purpose of having a SIM card to begin with?

My guess is that the computer thinks this is a micro sim (which it was) so it won't fit my nano sim slot, but it does and it works.  Except that Sprint doesn't seem to know how to enable it.

the internet is full of info from people who have done exactly this...trim the sim card to fit, yet it now seems I've got to wait a week and pay postage because the Sprint computers can't figure out that all that really matters is that the card is in place and connects to the phone.  Nearest Sprint store is over 100 miles, I was so mad at this I am close to moving carriers.  Fortunately, the Moto is an all carrier phone, so I'm no longer stuck if things keep irritating me like this. Any ideas why Sprint has done this, or are there really differences in nano SIMS that require a special one for each model phone?


Re: Can't use SIM card in different phone - why?

Flyinby, in order to activate a device, you need to perform a swap of both the SIM Card and the MEID in the activation system for the new device to work

therefore, even if you swap SIM cards, that alone will not activate the device.

Also, these two devices use each a different SIM card type. To get a SIM card for the Motorola phone, you can visit a Sprint store, my recommendation is to give them a call first for availability.


You can find a store and plan a visit using the Sprint Zone App on your smartphone, or on at


If you have any other questions or concerns, please let me know and have a great day!


Sprint Social Care Team.

Re: Can't use SIM card in different phone - why?

Thanks for your reply.

I did go through the online the phone I'm replacing, put in the MEID of the new phone, and attempted to enter the sim card number which was the same as my old phone, since I cut the micro card to nano specs and put it in. (this is not anything unusual, a google search on 'micro sim to nano sim' will produce myriads of how-to's and videos on trimming the larger cards to fact it's even done on full size sims to micro or nano; or, Amazon sells SIM card cutters for exactly that purpose. There are also numerous experiences along with the instructions detailing how it works without any issues). Check Wikipedia, paragraph 2 on the subject.

After putting in the new phone's MEID, I noticed the "use SIM from old phone" option was greyed out, so I manually put in the number, after which it told it was either not compatible with my new phone, or in use already.  The phone support people also could not enter the number for whatever reason, saying I needed a "new" SIM.  This would be easy if I had a corporate Sprint store handy, but the closest is 100+ miles.  Our local (20 miles) Sprint store told me they "might" have one if I bring the phone in, but they weren't sure, and it would cost me maybe $30, where Sprint told me it's free from them, and should also be free at the local (3rd party) Sprint store.  It's not.


I'm guessing that the computerized phone swap process thinks my original SIM is a micro SIM and won't fit the new phone, being completely ignorant of the fact that they can be trimmed to fit the smaller slot (contacts are the same for all).  So it says it's "not compatible" and how do you argue with a computer, or say "let me put it in and try to activate the phone, and let's see", which would probably work fine.


Sprint will mail me one, but that can take up to a week, and even with the $13 expedited shipping I had to pay, it won't get here for several days due to the weekend.  I wouldn't mind this if it were necessary, but it seems that the computerization or mechanization of the process has removed the ability to override any issue that the computer is ignorant of, or if there is a way, no one at support knows about it.


SIM cards were purposed to be able to change phones while retaining subscriber information for activation, and in some cases to store contacts etc. to ease the transfer.  What good are they if they can't be transferred between phones?  I realize that if my S5 had a nano sim this wouldn't have happened, but since the different sizes are just more plastic around the same device, what does it matter if I trimmed a larger one down or it was originally trimmed to that size?


Basically, I'm just irritated that for no good reason, I have to wait several days, wondering if it will get here in time for a trip next week, or if I will be doing without a phone for that time (the S5 is so difficult to unlock that it's basically could be having a heart attack and die while trying to get the screen to stay on.  I'm all for computerizing processes to streamline things, but when they also cause grief because something was left out of the program, that's a different story.  All they need to do is to allow an override of the "incompatible sim" issue when swapping phones, or tell it not to worry about the size, or just to warn the user that the old one is a different size than the new phone requires.


Re: Can't use SIM card in different phone - why?

since that device is not sold by sprint it must be added into their in a ticket must be created to add it in and takes around 3 days to complete. this is the same exact scenario for anyone getting a replacement Nexus phone directly from must be added into the carriers system since its considered a unknown device.
I like many others come onto this site for assistance and to help others. Marking a reply as helpful or correct helps others with like issues when they try to search the site for assistance. I do not work for Sprint and my suggestions and or opinions are my own. *************************************************************************************************************
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