Looking to switch? Perhaps you moved to a new area where your current carrier doesn’t have great coverage. Or maybe you want to lower your monthly bill and found a better deal. No matter your reason, it’s perfectly legal to unlock your iPhone — if it’s not already unlocked — and switch to a new carrier. And there’s now an easy way to check to see if your iPhone is locked to your current carrier’s network.
Your iPhone needs to be fully paid off, however, before you jump ship. If you are in the middle of an installment plan, you’ll need to complete all payments before your carrier will let you leave.
Wait, my iPhone might already be unlocked?
If you paid full price upfront for your iPhone, then it’s likely unlocked. If you purchased it through AT&T, Verizon or another carrier, then it’s probably locked to that carrier’s network.
How do I know if it’s locked or unlocked?
Apple last year added a way to check if your iPhone is locked or unlocked that doesn’t involve calling your carrier and navigating to a human that can answer this simple question. As long as you are running iOS 14 or iOS 15, you can go to Settings > General > About and scroll down to Carrier Lock. If you see No SIM restrictions on this line, then — good news! — your iPhone is unlocked. If you see SIM locked, however, then you probably still have some payments to make before your iPhone is fully paid.
What if it’s locked?
If your iPhone is paid up and still not unlocked, then you’ll need to contact your carrier to request an unlock. Before you call, though, you may be able to initiate the unlocking process from your carrier’s site. Check out the device unlock pages from AT&T, T-Mobile and Verizon — you may need to wait a day or two for your request to be completed. Once confirmed, you’re good to go.
Once your new service is up and running, don’t forget to cancel your old contract.
OK, so how do I remove the SIM card?
Back up your iPhone, power it off, grab the SIM-eject tool that may have been included with your iPhone or a safety pin and pop it into the little hole next to your SIM tray to eject it.
The SIM is out. Now what?
All that’s left to do now is to put your the SIM card from your new carrier in the tray and slide it back into your phone.
Yep, one more thing: Take your phone number with you. You should be able to transfer your number without issue from one carrier to another, but it’s a good idea to check for yourself. In the US, you can check with the major carriers — AT&T, T-Mobile and Verizon — to see if your number is eligible to port.
Source from www.cnet.com