If a cell phone is locked, it means that the phone can only be used on one specific carrier's network, like only on Verizon service, or only on AT&T. Carriers will install software on the phone to lock it to their network.
When a handset is locked it means it will only work with the provider that you bought it from. If your phone is locked it won't automatically become unlocked when your contract expires with your provider. You'll have to specifically ask your carrier to unlock it.
Android devices (Samsung, Google, etc.
If you see only one carrier displayed, it likely means your phone is locked to that particular carrier and won't be able to accept a new carrier until this is changed. Please contact your carrier to have the phone unlocked.
Carriers, upon request, will unlock mobile wireless devices no later than one year after initial activation, consistent with reasonable time, payment, or usage requirements.
If you live in the United States, the answer is yes. It is legal to unlock your iPhone or another cell phone. Ready to unlock your iPhone and move it to another phone company? Find out how in How to Unlock the iPhone on AT&T, Verizon, Sprint and T-Mobile.
iPhone: $20 to $80 for some carriers and $120 to $220 for premium & high guaranteed unlocks. Samsung: Start at $3 and range between $20 to $30 for higher-end models. Models with some carriers even cost up to $80.
Carriers lock phones to prevent their users from switching to other providers before their contract is up. Cell phones are costly, with prices soaring into the thousands. However, many manufacturers and carriers provide contracts with payment plans to allow interested buyers to pay off their phones over time.
Your phone cannot be re-locked to different network. Any compatible SIM card can be inserted, and as long as you have an account and credit with that network, you'll be able to make calls, send SMS, and perhaps even get online.
Can my mobile service provider refuse to unlock my phone because I owe them money or am currently under contract? Yes. Providers do not have to unlock devices for existing or former customers that are not in good standing.
You can ask your provider to unlock your phone. If you're out of your initial phone contract, the company must do this for free. Even if you're still within the contract term, all the major networks should allow you to unlock the device without a fee. Most phone networks ask you to fill in an online form.
Sim locked simply means the sim has a sim pin, which has nothing to do with the iPhone. Enter the PIN number for the sim, or get a new sim that is not locked.
Performing a factory reset on a phone returns it to its out-of-box state. All your apps and data are wiped clean and you have to go through the setup process again. If a third party reset the phone, the codes that changed the phone from locked to unlocked are removed.
According to the claims of major U.S. wireless carriers, unlocking a phone bought after January 26 without your carrier's permission violates the Digital Millennium Copyright Act (“DMCA”) whether the phone is under contract or not. In a way, this is not as bad as it sounds.
Unlock The Phone On Your Own
First of all, you have to turn off your mobile phone and take out the SIM card. Then turn on the device without the SIM card and wait for it to show a message with the instruction to insert the SIM card. From that moment you will need to write the IMEI code to unlock the phone.
Many phones sold by carriers come "locked" to that carrier. A "locked" phone can only be used with that carrier; it cannot be used with another carrier's service. (Not counting roaming.) This lock can usually be removed by entering a special code or numeric password.
Carrier locks work at SoC/bootloader level. In simple terms the modem - which has its own Baseband Processor - is tuned to certain frequencies / bands or programmed to register with only one MCC/MNC which identifies a universally unique carrier.
Good to know:
It usually takes a few minutes to approve your request, but it can take up to 48 hours.
According to the Federal Communications Commission, however, the carrier must unlock your phone for free after you've fully paid off the device (or coughed up an early termination fee).
iPhones sold in Apple Stores are unlocked and can take a sim card from any supported carrier.
You can sell your iPhone device whether it is locked or not. There are several kinds of locks that may affect the efficiency of your device, including activation lock, password lock, and iCloud lock.
You can use any SIM card you intend to use. Due to this, jailbreaking is the most common solution to many issues of iOS devices. After jailbreaking your device, you can unlock carrier lock and use the mobile network of your choice. So, you don't need to use the SIM card of the original carrier.
But before jailbreaking, you may ask: Does jailbreak remove carrier lock? Or, can I jailbreak my iPhone to unlock carrier? Yes, absolutely. As we mentioned, you can get more freedom after you unlock iPhone with jailbreak, including unlocking carrier.
Your iPhone may be locked to your network provider. Unlocking your iPhone means you can use it with different network providers. To contact your network provider and unlock your iPhone, follow these steps. You can find out if your iPhone is locked by going to Settings > General > About.