Apple this week closed a loophole that allowed customers to purchase an unlocked iPhone on a monthly payment plan from T-Mobile or Verizon.
Going forward, if you finance an iPhone through T-Mobile or Verizon, the iPhone will be locked to either carrier until the device is fully paid off. This policy already applied to iPhones that are financed through AT&T, and now it extends to T-Mobile and Verizon, which ends the ability to get an unlocked iPhone with carrier financing in the U.S.
Here was the relevant fine print on Apple's website on July 14:
In most cases, yes. An iPhone purchased from apple.com is unlocked. Once your new iPhone is activated, it remains unlocked, which means you can use it with any network that provides service for iPhone. However, if you buy an iPhone with an AT&T Installment Plan, your iPhone will be locked to AT&T and will only work on the AT&T network for the term of your Installment Plan agreement.
The updated text as of July 15:
In most cases, yes. An iPhone purchased from Apple is unlocked. Once your new iPhone is activated, it remains unlocked, which means you can use it with any carrier that provides service for iPhone. However, if you choose to finance an iPhone through the AT&T Installment Plan, T-Mobile Equipment Installment Plan, or Verizon Device Payment Program, your iPhone will be locked to the carrier until paid in full.
A carrier-locked iPhone is limited to the carrier it was purchased through, and this even prevents you from using an eSIM from another carrier while traveling. On the other hand, an unlocked iPhone can be used with any carrier.
