For information about making international calls from your home area, including rates and other charges that may apply, contact your carrier or go to your carrier’s website.When traveling abroad, you may be able to use iPhone to make calls, send and receive text messages, and use apps that access the Internet, depending on available networks.Enable international roaming: Contact your carrier for information about availability and fees.Important: Voice, text message, and data roaming charges may apply. To avoid charges when roaming, turn off Voice Roaming and Data Roaming.If you have an iPhone 4S or later that’s been activated to work on a CDMA network, you may be able to roam on GSM networks if the phone has a SIM card installed. When roaming on a GSM network, iPhone has access to GSM network features. Charges may apply. Contact your carrier for more information.Set network options: Go to Settings > General > Cellular to: Turn data roaming on or off. Turn cellular data on or off. Turn voice roaming on or off (CDMA). Use GSM networks abroad (CDMA).
Turn off cellular services: Go to Settings, turn on Airplane Mode, then tap Wi-Fi and turn Wi-Fi on. Incoming phone calls are sent to voicemail. To resume cellular service, turn Airplane Mode off.Automatically add the prefix or country code for calls to the U.S.: (GSM) Go to Settings > Phone, then turn on Dial Assist. This lets you use contacts and favorites to make calls while abroad.Choose a carrier: Go to Settings > Carrier. This option is available only when you’re traveling outside your service provider’s network, and for carriers that have roaming agreements with your provider. Get voicemail when visual voicemail isn’t available: Dial your own number (with CDMA, add # after your number), or touch and hold “1” on the numeric keypad.