We’ve been customers with Verizon for a long time but are thinking of moving to T-Mobile where we can get unlimited everything for quite a bit less a month. The only issue is that we want to take our phones (iPhone 5 & 4s) with us and I’m not getting clear answers to if they’d work on a different network.

• Best Buy Mobile says we can’t.
• T-Mobile’s mall kiosk says yes on the iPhone 5, no on 4s.
• Costco says absolutely not.
• Target (BrightSpot) sales people say yes to both.
• T-Mobile via Twitter says to check out their help file which says yes.
• Verizon via Twitter says yes to the iPhone 5, but no to the 4s.
• The internet says yes, no, maybe.
• The T-Mobile store I went to said that the iPhone 5 is a yes, and the 4s is a maybe. If I had the 4s on hand when I went in, they could have told me for sure.

The main issue is that Verizon’s network is CDMA and T-Mobiles is GSM. However, both phones are global phones so they should be able to work on either network.

Starting with the iPhone 4s, Apple made iPhones compatible with either network, but the wireless companies still tried to keep them locked to their network only. Until recently, you couldn’t take a Verizon iPhone to AT&T or T-Mobile. However, that looks like it’s changing.

On August 1st, President Obama put into law a bill that allowed customers to unlock their phones and move them to any other compatible network. In theory, this should mean that I can take both iPhones to T-Mobile.

Unfortunately, no one has the answers. Everyone has an opinion one way or another, but it’s confusing. Even the T-Mobile store employee was a bit confused which is why he wanted to have the phone in hand before giving a definitive answer.

For now, I’m still not sure on the right answer. I’m going to try and get into another T-Mobile store with the iPhone 4s to see if we can get a definitive answer. Hopefully I can get this figured out in the next month or so.

Update A Verizon iPhone 4S is not compatible. We put in a T-Mobile SIM card and it wouldn’t recognize the network.

Update 2 A Verizon iPhone 5 works just fine on T-Mobile with the exception of LTE. That’s not supported. But 4G works.