Turn off cellular data
You can temporarily turn off cellular data to prevent apps from using the cellular network to send or receive data. Here's what happens when you turn off cellular data:
- You won't see the cellular data icons in the status bar (for example, LTE or 3G).
- You won't be able to send or receive MMS messages. You can still send and receive SMS and iMessages (text or multimedia) when connected to a Wi-Fi network.
- You won't be able to retrieve or listen to new Visual Voicemail messages.
- You won't be able to use Personal Hotspot.
To turn off cellular data, tap Settings > Cellular on your iPhone or Settings > Cellular Data on your iPad.
Current Period under Cellular Data Usage is an accumulation of your data used since the last time the stats were reset. You can tap Reset Statistics at the bottom of the screen.
When you turn off cellular data, your data services like email, web browsing, push notifications, and others will use Wi-Fi. When you turn on cellular data, you might be charged for using certain features and services that transfer data, such as Siri and Messages.
Depending on your carrier and device model, you might have additional options:
- Enable LTE or 3G.
- 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, your device won't have cellular (data or voice) service.
- Turn Data Roaming on or off: Data Roaming allows you to access the Internet over a cellular data network when you're in an area that isn't covered by your carrier's network. When you're traveling, you can turn off Data Roaming to avoid roaming charges.
View and adjust data usage
Some apps from the App Store use the Apple Push Notifications to alert you of new data. Apps that use push notifications (such as instant messaging or social media apps) will use cellular data. To turn off push notifications, go to Settings > Notifications.
To view the cellular data usage for your apps, tap Settings > Cellular. You can turn cellular data on or off for each app. Contact your carrier if you have questions about your cellular data usage.
With iOS 9, you can use Wi-Fi Assist to switch to cellular when Wi-Fi becomes weak or unreliable. The status bar will show whether your device is using a cellular network or Wi-Fi. Wi-Fi Assist isn’t available if you're using data roaming. You can use Wi-Fi Assist with all iOS devices that support iOS 9, except for these models: iPhone 4s, iPad 2, iPad (3rd generation), and iPad mini (1st generation).
Exchange ActiveSync accounts are handled separately from other Mail and Calendar accounts. Exchange ActiveSync accounts will continue to use cellular data even if you turn off cellular data for Mail and Calendar. To view your Exchange ActiveSync cellular data usage, tap Settings > Cellular > System Services.
When your device is connected to Wi-Fi, any FaceTime Video or Audio calls you make will use the Wi-Fi network. If your router loses its Internet connection, or if the Wi-Fi connection degrades, you'll stay connected to the Wi-Fi network, but your device will route the data over cellular data.
You can set apps like Mail to fetch data wirelessly at specific intervals. The more frequently your device fetches email or other data, the faster data is consumed.
- To fetch new data manually, tap Settings > Mail, Contacts, Calendars > Fetch New Data. Turn off Push, then tap Manually.
- To increase the fetch interval, tap Settings > Mail, Contacts, Calendars > Fetch New Data and tap Hourly.
This is a global setting, which means it applies to all apps that don't support push services.