Can You Set a Data Limit on iPhone? What Works Instead

Why there is no data limit on iPhone

Apple's cellular settings let you see usage and switch data on or off, app by app. There is no field for a monthly allowance, no warning level and no automatic cut-off. Even carriers' own guides say so: Vodacom notes that iPhones don't offer the built-in mobile data cut-offs that Android does.

Screen Time doesn't fill the gap either. It limits how long apps can be used, and when. It doesn't measure or cap data, so a one-hour limit on a video app can still use a lot of data in that hour.

Turn off cellular data for heavy apps

This is the closest thing iPhone has to a hard limit. An app with cellular data turned off only works on Wi-Fi.

1. 1Open Settings > Cellular (called Mobile Data or Mobile Service in some countries).
2. 2Scroll down to the list of apps. Each one shows how much it used.
3. 3Turn off the switch next to any app you only need on Wi-Fi, such as video, photo backup or game apps.

You can also turn off Cellular Data at the top of the same screen. Then every app uses Wi-Fi only until you turn it back on.

Turn on Low Data Mode

Low Data Mode doesn't stop data, but it cuts the background use you don't see. It pauses automatic updates and backups, turns off Background App Refresh and lowers streaming quality.

1. 1On 4G (LTE), go to Settings > Cellular > Cellular Data Options and turn on Low Data Mode.
2. 2On 5G, go to Settings > Cellular > Cellular Data Options > Data Mode and choose Low Data Mode.

Stop iPhone using cellular when Wi-Fi is weak

On current iOS versions, Wi-Fi Assist has been replaced by Connectivity Assist. When it is on, iPhone uses cellular data alongside Wi-Fi when the Wi-Fi is weak or busy. That can use data while you think you are on Wi-Fi.

1. 1Open Settings > Wi-Fi.
2. 2Scroll down and turn off Connectivity Assist. On older versions, the setting is called Wi-Fi Assist and sits at the bottom of the Cellular screen.

Reset the counter on your billing day

The usage total in Settings > Cellular isn't monthly. It counts everything since it was last reset. To compare it with your plan, scroll to the bottom on the day your plan renews and tap Reset Statistics. Set a monthly reminder so you don't forget. For more on reading this screen, see How to Check Data Usage on iPhone.

Use your carrier's data alerts

Your carrier is the one place that can warn you before your plan runs out. Most send texts on their own, and some let you choose the level.

• Verizon: in the My Verizon app, you can turn on data usage alerts and pick levels such as 50%. Verizon doesn't send usage alerts on Unlimited plans.
• AT&T: sends a text at 75% of your data on current unlimited plans, and at 75% and 100% on plans with a fixed allowance. You can turn alerts on or off under Communications in your AT&T account profile.
• T-Mobile: sends a free text when you are close to your plan's allowance and another when it is used up. You can check usage in the T-Life app.
• EE (UK): texts you at 80% of your monthly allowance and again when you run out. The EE app shows your full usage under Manage.
• O2 (UK): texts you at 80% and 100% of your allowance. The My O2 app shows what is left under My Allowances.

The catch is that these alerts are monthly. They tell you when most of the plan is gone, not that today was a heavy day.

Dataly can't show per-app usage on iPhone, because Apple doesn't allow it. For that, use the app list in Settings > Cellular.

Which to use

• To stop an app using data: turn off its cellular switch.
• To use less without thinking about it: Low Data Mode, with Connectivity Assist off.
• To know before the plan runs out: carrier alerts, plus a daily limit in an app like Dataly.

If your data still goes faster than expected, read Why Is My Data Running Out So Fast?.