Where to find your data usage on iPhone
Your iPhone tracks how much mobile data each app uses, and you can see the total in Settings. Open Settings, tap Cellular, and scroll down to see "Cellular Data" at the top — this shows your total usage since the last reset. Below that, you'll see a list of every app and how much data it has used. The number next to each app is what matters if you're trying to figure out which one is consuming your plan.
The data shown here resets on a schedule you set yourself, not on your billing date. Many people reset it monthly to match their phone plan, but you can reset it whenever you want. If the number seems wrong or outdated, you may need to reset the counter and start fresh.
Key Takeaways
- Open Settings, tap Cellular, and look at the list below "Cellular Data" to see which apps use the most data.
- The total shown resets on a schedule you choose, not automatically on your billing date.
- Turning on Low Data Mode in Settings limits background activity and can reduce data use across most apps.
- Your carrier's own app or website shows your actual plan usage and how much data you have left before overage charges.
- Wi-Fi usage does not count toward your mobile data plan, even though iPhone tracks it separately in the same menu.
How to reset your data counter
The number iPhone shows you is only useful if you reset it on the same day your billing cycle starts. To reset it, go to Settings > Cellular, scroll to the bottom, and tap "Reset Statistics." This clears the counter to zero and starts counting fresh from that moment. Write down the date you reset it so you know when to reset it again next month.
If you reset it in the middle of the month by accident, you can do it again — there's no limit to how many times you can reset. Just remember that once you reset, the old number is gone. If you need to know your usage for a specific period in the past, your carrier's app will have that history instead.
Understanding the difference between carrier data and iPhone data
The number in your iPhone Settings may not match the number your carrier shows you. This happens because your carrier counts data differently — they include overhead data that iPhone doesn't count, and they may count data from a different time period. Your carrier's number is the one that matters for your bill, so if you're close to your limit, check your carrier's app or website instead of relying on iPhone's counter.
To see your actual usage and remaining data, open your carrier's app (AT&T, Verizon, T-Mobile, or whoever you use) or log into their website. Most carriers update this number in real time or within a few hours. This is also where you'll see if you're about to hit an overage charge or if you have unlimited data.
Turning on Low Data Mode to reduce usage
If you're running low on data before your billing cycle ends, Low Data Mode tells apps to use less data in the background. Go to Settings > Cellular > Cellular Data Options > Low Data Mode and turn it on. When it's on, apps won't read large files, won't refresh in the background, and won't stream video at full quality unless you're actively using them.
Low Data Mode works across most apps, but some may not respect it — particularly older apps or ones that don't have a data-saving feature built in. Video apps like YouTube and Netflix usually have their own quality settings that override Low Data Mode, so you may need to lower the video quality in those apps separately. Low Data Mode stays on until you turn it off, so remember to disable it once you're past your limit or your billing cycle resets.
Checking data usage for individual apps
If one app is using far more data than the others, you can see exactly how much. In Settings > Cellular, find the app in the list and look at the number next to it. That's the total data it has used since you last reset the counter. Apps like video streaming, social media, and maps use the most data because they read large files or constantly refresh location.
If an app's number seems too high, you have two choices: turn off its cellular permission or uninstall it. To turn off cellular permission, go to Settings > Cellular, find the app, and toggle off the switch next to it. The app will still work on Wi-Fi, but it won't use any mobile data. This is useful for apps you only need at home or at the office.
Why your data usage might be higher than expected
Background app refresh is a common reason data usage climbs without you noticing. Apps update their content in the background even when you're not using them — email checks for new messages, weather updates the forecast, social media refreshes your feed. To see which apps are doing this, go to Settings > General > Background App Refresh and turn off the toggle for apps you don't need to update constantly.
Automatic updates and iCloud backups also use data if you're not on Wi-Fi. Go to Settings > App Store and turn off "App Updates" under Automatic Downloads if you want to update apps only when you choose to. For iCloud, go to Settings > [Your Name] > iCloud > iCloud Backup and make sure it's set to back up only on Wi-Fi, not on cellular.
Setting a data warning or limit
iPhone can warn you when you're approaching your data limit, though the warning is less precise than your carrier's warning. Go to Settings > Cellular > Cellular Data Limit and set a number close to your plan's limit. When you reach it, iPhone will warn you and can turn off cellular data automatically so you don't accidentally go over.
This feature is useful as a backup, but don't rely on it alone — your carrier's warning is more accurate because it counts data the way your bill does. Set your iPhone limit slightly below your actual plan limit so you have a buffer. If you have unlimited data, you don't need to set a limit at all.
Frequently Asked Questions
Why does my iPhone show more data usage than my carrier does?
Your carrier counts overhead data that iPhone doesn't track, and they may count data from a different time period. Your carrier's number is what appears on your bill, so use that as your source of truth. iPhone's counter is useful for seeing which apps use the most, but not for knowing your exact plan usage.
Does Wi-Fi usage count toward my mobile data plan?
No. Wi-Fi data never counts toward your mobile plan, even though iPhone tracks it separately in the same menu. You can see Wi-Fi usage in Settings > Wi-Fi > [Network Name], but it has no effect on your bill or your data limit.
Can I see data usage for a specific date or week?
iPhone only shows total usage since your last reset, not broken down by date. Your carrier's app usually shows daily or weekly breakdowns. If you need detailed history, check your carrier's website or app instead of relying on iPhone's counter.
What happens if I turn off cellular data completely?
Your phone will only work on Wi-Fi. Calls, texts, and data will not work unless you're connected to Wi-Fi. You can turn it back on anytime in Settings > Cellular. This is useful if you want to avoid data charges while traveling, but you'll lose service outside of Wi-Fi areas.
Does Low Data Mode slow down my internet speed?
Low Data Mode doesn't slow your connection itself — it just tells apps to use less data by reducing quality and limiting background activity. You may notice slower downloads or lower video quality because apps are using less bandwidth, but your actual internet speed is the same.