Cell phone service providers routinely program the cell phones they offer to their customers so that these phones cannot be used with another carrier. Phones that are carrier-specific are referred to as being locked. This tactic often keeps users from switching from one provider to another, but can be frustrating if you have good reason to change, but don’t want to lose your current phone.
People who travel to Asia or Europe are often faced with a dilemma when it comes to using their cell phones. U.S. cell phone carriers charge international travelers high roaming fees, often making using a cell phone overseas cost-prohibitive. The solution is to purchase a SIM card from the cell phone company in the country in which you are traveling. Many international companies sell cards pre-loaded with minutes and if your phone is unlocked, you can switch out the SIM cards and use your phone.

The ability to Unlocked cell phones depends on the type of phone you have and the technology associated with it. Currently, cell phones are equipped with either Code Division Multiple Access (CDMA) or Global System for Mobile Communication (GSM). CDMA technology utilizes the entire available spectrum, enabling users far greater capacity that GSM, which assigns each user a subscriber identity module (SIM) card. This card holds all the user’s phone settings, contacts, notifications, and call history.

While a CDMA phone offer better coverage, because it must be programmed by the carrier and does not have a removable memory card, it cannot be unlocked. With a GSM phone, however, it is often possible to switch the SIM card from one phone to another, allowing service to continue uninterrupted.

This is not always possible, however. Some phones are programmed with software that links the SIM card to the serial number of a specific phone. The serial number of the phone must match the code on the SIM card in order for the phone to work. This restricts switching the SIM card to another phone or the specific phone to another SIM card.

There are four ways to unlock cell phones. Start by calling your service provider and asking them the procedure for unlocking a phone. Depending on the company’s policy, they may charge a fee to do this. You may also have to agree to remain with the company for a specific amount of time. If the terms are acceptable, the process is simple. The CSR will give you a code, which you can enter into your phone and it will be unlocked. Another method is to use a company that offers a fee to unlock cell phones. To find one of these companies, search for “unlock cell phones” using your favorite Internet search engine.

You can also unlock cell phones by using special equipment such as a universal unlock SIM card, a data card unlocker, and a data cable with standalone software. This equipment can be pricey, however, and is most often used by professionals operating cell phone unlock services.

The final way to unlock cell phones is by using the online community. There are numerous phone unlocking forums and message boards where people share information, including unlock codes, company policies, and other pertinent information.

Once your phone is unlocked, you can install a new SIM card and switch providers. You may want to check the terms of the original provider’s contract, however, in that many cell phone companies charge hefty fees to drop service.
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