View or change cellular settings on iPhone
Turn cellular data and roaming on or off, set which apps and services use cellular data, see call time and cellular data usage, and set other cellular options.
Note: For help with cellular network services, voicemail, and billing, contact your wireless service provider.
If iPhone is connected to the Internet via the cellular data network, an icon identifying the cellular network appears in the status bar.
LTE, 5G E, 4G, and 3G service on GSM cellular networks support simultaneous voice and data communications. For all other cellular connections, you can’t use Internet services while you’re talking on the phone unless iPhone also has a Wi-Fi connection to the Internet. Depending on your network connection, you may not be able to receive calls while iPhone transfers data over the cellular network—when downloading a webpage, for example.
GSM networks: On an EDGE or GPRS connection, incoming calls may go directly to voicemail during data transfers. For incoming calls that you answer, data transfers are paused.
CDMA networks: On EV-DO connections, data transfers are paused when you answer incoming calls. On 1xRTT connections, incoming calls may go directly to voicemail during data transfers. For incoming calls that you answer, data transfers are paused.
Data transfer resumes when you end the call.
If Cellular Data is off, all data services use only Wi-Fi—including email, web browsing, push notifications, and other services. If Cellular Data is on, carrier charges may apply. For example, using certain features and services that transfer data, such as Siri and Messages, could result in charges to your data plan.
Turn Cellular Data on or off
Go to Settings > Cellular. The following options may also be available:
Turn Voice Roaming on or off: (CDMA) Turn Voice Roaming off to avoid charges from using other carrier’s networks. When your carrier’s network isn’t available, iPhone won’t have cellular (data or voice) service.
Turn Data Roaming on or off: Data Roaming permits Internet access over a cellular data network when you’re in a region not covered by your carrier’s network. When you’re traveling, you can turn off Data Roaming to avoid roaming charges.
Enable or disable 4G/LTE: (availability varies by carrier and region) Using 4G or LTE loads Internet data faster in some cases but may decrease battery performance. There may be options for turning off 4G/LTE or for selecting Voice & Data (VoLTE) or Data Only.
Voice & Data: (some carriers) Choose LTE to load data faster. (This also turns on VoLTE.) Choose slower speeds to increase battery life.
Set up Personal Hotspot: Personal Hotspot shares the Internet connection on iPhone with your computer and other iPhone, iPad, and iPod touch devices. See Share your iPhone Internet connection in this guide.
Turn Wi-Fi Assist on or off: If Wi-Fi connectivity is poor, Wi-Fi Assist uses cellular data to boost the signal.
Note: Using data over a cellular network may incur additional fees.
Set whether cellular data is used for apps and services
Go to Settings > Cellular, then turn Cellular Data on or off for any app that can use cellular data.
If a setting is off, iPhone uses only Wi-Fi for that service.
Lock your SIM card
If your device uses a SIM card for phone calls or cellular data, you can lock the card with a personal identification number (PIN) to prevent others from using the card. Then, every time you restart your device or remove the SIM card, your card locks automatically, and you’re required to enter your PIN. See Use a SIM PIN for your iPhone or iPad.