How to Reduce iPhone Data Usage Without Turning Cellular Data Off

If your cellular plan has a limited data allowance, you do not necessarily need to switch cellular data off every time you leave Wi-Fi.

The iPhone includes Low Data Mode, which reduces cellular usage by limiting some automatic updates and background activity.

Turn on Low Data Mode

Open Settings > Cellular > Cellular Data Options.

Choose Data Mode, then select Low Data Mode.

The exact options available can depend on your iPhone, carrier and region.

Low Data Mode does not mean “no data.” Apps you actively use can still access the internet. Instead, the setting is intended to reduce less-important background usage.

You can use it for Wi-Fi too

Low Data Mode is also available for individual Wi-Fi networks.

Open Settings > Wi-Fi, tap the information button beside the network, and turn on Low Data Mode.

That can be useful when your “Wi-Fi” connection ultimately comes from a limited source such as another phone's hotspot or a metered internet connection.

Watch roaming separately

Low Data Mode and Data Roaming solve different problems.

When traveling outside your carrier's normal coverage area, check Data Roaming separately. Apple says turning Data Roaming off can help avoid roaming charges.

Carrier rules and international plans vary, so confirm the terms of your actual cellular plan rather than assuming a phone setting eliminates every possible charge.

Low Data Mode is best thought of as a conservation setting: you still have connectivity, but the iPhone becomes more restrained about background data use.

Sources and Further Reading

Apple iPhone User Guide: View or change cellular data settings and manage Wi-Fi settings — https://support.apple.com/guide/iphone/view-or-change-cellular-data-settings-iph3dd5f213/27/ios/27