iPhone SIM unlocking

United States

Most iPhones were and are still sold with a SIM lock, which restricts the use of the phone to one particular carrier, a common practice with subsidized GSM phones. Unlike most GSM phones however, the phone cannot be officially unlocked by entering a code. The locked/unlocked state is maintained on Apple's servers per IMEI and is set when the iPhone is activated.

While the iPhone was initially sold in the US only on the AT&T network with a SIM lock in place, various hackers have found methods to "unlock" the phone from a specific network. Although AT&T and Verizon are the only authorized iPhone carriers in the United States, unlocked iPhones can be used with other carriers after unlocking. More than a quarter of the original iPhones sold in the United States were not registered with AT&T. Apple speculates that they were likely shipped overseas and unlocked, a lucrative market before the iPhone 3G's worldwide release. iPhones are unlocked by users who wish to use networks other than AT&T or Verizon's.

AT&T has stated that the "iPhone cannot be unlocked, even if you are out of contract". On March 26, 2009, AT&T in the United States began selling the iPhone without a contract, though still SIM-locked to their network. The up-front purchase price of such iPhone units is often twice as expensive as those bundled with contracts. Outside of the United States, policies differ, especially in US territories and insular areas like Guam, where GTA TeleGuam is the exclusive carrier for the iPhone, since neither AT&T nor Verizon have a presence in the area.

United Kingdom

Operators O2, Orange, 3, Vodafone, T-Mobile, as well as MVNO Tesco Mobile sell the device in the UK under subsidised contracts, or for use on pay as you go. They are locked to network initially, though are usually able to be unlocked either after a certain period of contract length has passed, or for a small fee. The iPhone 4 in the UK is also currently sold unlocked without a contract for full retail price for use on any network the user chooses, but only when bought directly from Apple (either online or in their physical shops).

Australia

Five major carriers in Australia, (Three, Optus, Telstra, Virgin Mobile, and Vodafone), offer legitimate unlocking, now at no cost for all iPhone devices, both current and prior models. The iPhone 3GS and the iPhone 4 can also be bought unlocked from a Apple Retail Store, or the Apple Online Store.

Denmark

It is possible to purchase the iPhone directly from Apple According to Danish law, the iPhone can be unlocked after six months on contract, or earlier by paying a fee of DKK 500 (approx. €70).

TDC does not lock their iPhones

France

In France, the iPhone is locked on the Wireless purchased from (Orange, SFR, Bouygues Telecom or Virgin Mobile), but can also be bought unlocked in Apple stores. Phones that were initially locked to a carrier are unlocked for free after a certain portion of the bundled contract's fixed term is up, or for a fee at any time before that.

Germany

In Germany, the iPhone 3GS or iPhone 4 may be purchased without a SIM-lock directly from Apple. The iPhone may also be purchased through T-Mobile, Vodafone, and O2, three of the four major German mobile network carriers.

Other countries

The iPhone is also available without any SIM lock for full retail price in some countries. Vendors in countries including Austria, Belgium, Canada, China, Cyprus, Ecuador, Finland, Greece, Hong Kong, Italy, Ireland, Israel, Kazakhstan, Mexico, the Netherlands, New Zealand, Norway, Romania, Russia, Saudi Arabia, Singapore, Spain, South Africa, Sweden, Taiwan, Pakistan, Bangladesh, Thailand, Turkey and Vietnam sell iPhones not locked to any carrier.In India, iPhone is officially SIM locked to either Vodafone or Airtel.