If yous're buying or selling a used iPhone, it'south helpful to know if it's locked to a carrier or unlocked. Also, you lot'll need to brand sure it doesn't have an activation lock. Here'due south how to cheque both.

How to Check if an iPhone Is Locked to a Cellular Carrier

If yous have a carrier lock on your iPhone, it means you can only use the iPhone with a particular mobile phone service provider. If the iPhone is unlocked, you tin use it with any cellular carrier. Luckily, it's like shooting fish in a barrel to check whether your iPhone is locked or unlocked.

First, open up the Settings app on your iPhone by borer the grey gear icon.

In Settings, tap "General," then select "Most."

In General settings, tap "About."

On the "About" screen, scroll downward to the very lesser of the folio and locate the "Carrier Lock" item. If you run into "No Sim Restrictions," then your iPhone is unlocked. If it says "SIM Locked" (or something similar), then your iPhone is locked to a particular carrier.

Look beside "Carrier Lock" to see if the iPhone is locked.

If your iPhone is locked and you want to unlock it, you tin contact your carrier and ask for an unlock. They might not exercise it, depending on the status of your account with them. Apple notes on its site that it cannot unlock a carrier lock for y'all—only the carrier can do that.

RELATED: How to Unlock Your Cell Phone (So You Tin can Bring Information technology to a New Carrier)

How to Check If an iPhone Is "Activation Locked" by Apple

Before buying or selling a used iPhone, make sure that Activation Lock is turned off on the device. Activation Lock is enabled automatically when "Notice My iPhone" is turned on, and information technology prevents some other person from using the device without the original owner'southward Apple ID and password.

To check for Activation Lock on an iPhone, open Settings on the iPhone in question and tap your Apple ID.

In iPhone Settings, tap your Apple ID name.

In Apple ID Settings, select "Find My."

In iPhone Settings, tap "Find My."

Nether "Discover My" settings, await at the "Find My iPhone" line. If it says "On," then Activation Lock is enabled. If information technology says "Off," so Activation Lock is disabled.

Look beside "Find My iPhone" and see if you see "On" or "Off."

If you lot'd like to disable Activation Lock on your iPhone, tap "Discover My iPhone" and flip the switch abreast "Find My iPhone" to the off position. If you're planning to sell or requite abroad your iPhone, you'll besides need to sign out of iCloud and perform a factory reset before handing the device over.

After the factory reset completes, you'll know that Activation Lock is truly disabled if you come across the "Hullo" screen inviting you to set upwardly your iPhone. If you're buying a used iPhone and it's been manufacturing plant-reset, make sure it shows y'all the standard "Hello" setup screen subsequently powering it on!

Otherwise, if the iPhone asks for an Apple tree ID and countersign to proceed with setup, it's still locked to the original owner. The owner can sign in and turn off "Find My iPhone" or log in to their Apple ID through the Apple website and remove the iPhone from their list of devices remotely. Good luck!

RELATED: How to Remove Activation Lock on an iPhone