You can unlock a SIM card if you have the correct code. Subscriber Identity Modules (SIM Cards) have built-in security to stop unauthorized use of the phone number. This can sometimes be as simple as the factory default '0000' four digit Personal Identification Number (PIN) code, or it can be a more elaborate four- to eight-digit code set by the user.

Sometimes it isn't even set, and the SIM Card can be hot-swapped from phone-to-phone without entering a PIN number. However, the SIM card will always have a Personal Unblocking Key (PUK Code). A PUK Code is set at the factory and is unique to each SIM card. This code can be used to unlock a SIM card if you don't have the PIN.

Insane prices for data when it’s cheaper to use a local SIM card with your unlocked phone. You Unlock Your Phone? How to Unlock Your Phone For Traveling. Sep 08, 2016 In other words: If you have a recent iPhone with 4G LTE service, you will not need to unlock your phone. How To Find Out If My Cell Phone Is Unlocked. If you have a locked 3G World Device phone with Verizon, you can use unlock code 000000 or 123456 or call 800-922-0204 for help. Do I need a SIM Card for my cell phone? This may be simple question, however, I see a lot of confusion out there on this issue and this guide will answer the questions. How Do I Unlock A Phone With A Pattern Lock here. Can Unlocked Iphones Work With Verizon. How To Unlock My Locked Android Phone on this page.