How do I unlock a carrier-locked iPhone?

How to unlock your iPhone for use with a different carrier - Apple Support

Settings > General > About > Carrier Lock might give you some indication as to who the carrier is.

Of course, iif you re the original purchaser of the phone, you should already know who the carrier is. (Difficult not to know if you bought the phone with their financing, or have been paying for cellular service from them.)

If this is a second-hand phone, you may. have trouble convincing the carrier to remove the lock. Carriers often will not remove their locks unless

• You are a customer or former customer in good standing, and
• Any contract on the phone is paid off in full

and if there is a non-paid-off contract on the phone with a previous owner, the carrier might refuse to give you the details about that contract for privacy reasons.

If your iPhone is carrier locked, you need to contact your carrier for help, not Apple.