Unexpectedly, users who purchased the iPhone 5 last week found that the Verizon version would accept SIM cards from AT&T and work on its slower 4G (3.5G) network. It will not work on AT&T's 4G LTE network.
According to the Associated Press, this is the first time Verizon has sold a phone that will work on a competing network with no unlocking procedure. Verizon spokeswoman Brenda Raney confirmed on Monday that Verizon does not plan to relock the device.
Sprint says its iPhone 5s are locked but customers in good standing for at least three months can request them unlocked for international use. AT&T will unlock your iPhone once your contract is up.