Mobile data is turned on through your phone's settings, usually in a menu labeled "Cellular," "Mobile Networks," or "Data"
Every smartphone has a master switch for mobile data. When it is off, your phone will not use your carrier's network to browse the web, check email, or stream video — it will only work on Wi-Fi. When it is on, your phone connects to your carrier's towers and uses the data included in your plan. The exact location of this switch depends on whether you have an iPhone or Android phone, but the principle is the same on both.
You may want mobile data off when you are on a limited plan and want to avoid overage charges, or when you are in an area with poor signal and want to preserve battery life. You may want it on when you are away from home and need to use apps or maps. Most people leave it on all the time and rely on Wi-Fi when they are at home to avoid using their monthly data allowance.
Key Takeaways
- On an iPhone, go to Settings, then Cellular, then toggle Cellular Data on or off.
- On Android, go to Settings, then Mobile Network or Cellular, then toggle Mobile Data on or off.
- When mobile data is off, your phone still receives calls and texts but cannot browse the web or use apps that need the internet.
- Turning mobile data off does not disconnect you from Wi-Fi — your phone will still use Wi-Fi networks you have connected to before.
- If you cannot find the setting, search your phone's settings for "mobile data" or "cellular data" and the search will take you directly there.
How to turn on mobile data on an iPhone
Open the Settings app and tap Cellular. You will see a toggle switch next to "Cellular Data" — tap it to turn the switch green, which means mobile data is on. If the switch is already green, mobile data is already enabled.
Below that toggle, you will see "Cellular Data Options." If you tap that, you can choose which apps are allowed to use mobile data and which must wait for Wi-Fi. This is useful if you have a limited plan and want to prevent certain apps from using data in the background. You can also see how much data each app has used in the last 30 days by scrolling down to "Cellular Data Usage."
How to turn on mobile data on Android
Open the Settings app. The next step depends on your phone's manufacturer, but look for a menu labeled "Network and Internet," "Connections," or "Mobile Networks." Tap it, then look for "Mobile Data" or "Cellular Data" and tap the toggle to turn it on. The toggle will turn blue or green when it is on.
If you cannot find it in those menus, open Settings and use the search box at the top — type "mobile data" and Android will show you the exact setting. Different manufacturers like Samsung, Google, and OnePlus arrange their menus differently, so searching is often faster than hunting through submenus.
What happens when mobile data is off
When mobile data is off, your phone will not connect to your carrier's network for internet. You can still make calls and send text messages, because those use a different part of the network. You can still receive calls and texts even if mobile data is off. However, apps that need the internet — like email, maps, social media, or web browsers — will not work unless you are connected to Wi-Fi.
If you are on Wi-Fi and mobile data is off, the Wi-Fi will still work. Your phone prioritizes Wi-Fi over mobile data anyway, so turning mobile data off does not affect Wi-Fi performance. The only time you notice the difference is when you are away from Wi-Fi and try to use an app that needs the internet.
When to turn mobile data off
Turn mobile data off if you have a limited monthly data plan and want to avoid overage charges. Many carriers charge $10 to $15 per gigabyte of data used beyond your plan, so if your plan includes 5 gigabytes per month and you use 6, you may be charged for that extra gigabyte. Turning mobile data off when you are at home or at work — where you have Wi-Fi — keeps you from using your monthly allowance on things you could do on Wi-Fi instead.
You might also turn mobile data off to save battery life. Searching for a mobile signal uses more power than connecting to a Wi-Fi network, so in areas with weak signal, turning mobile data off can extend your phone's battery by an hour or more. Some people turn it off at night to avoid notifications and calls, though airplane mode is a better choice for that because it also disables Wi-Fi.
Checking how much mobile data you have used
On an iPhone, go to Settings, then Cellular, then scroll down to "Cellular Data Usage." You will see the total amount of data used since the last time you reset the counter, and below that, a list of each app and how much data it has used. To reset the counter, scroll all the way down and tap "Reset Statistics." Most people reset this at the start of their billing cycle so they can track usage month to month.
On Android, go to Settings, then Network and Internet, then Mobile Network, then Data Usage. You will see a graph showing your data use over time and a list of apps below it. The exact menu names vary by manufacturer, but the search function will find it if you type "data usage." You can also set a data warning or limit here — if you set a limit, your phone will turn off mobile data automatically when you reach that amount.
Troubleshooting mobile data that will not turn on
If you toggle mobile data on but it does not stay on, or if the toggle is grayed out and you cannot tap it, restart your phone first. Power it off completely, wait 10 seconds, and power it back on. This fixes most temporary glitches with mobile data.
If restarting does not work, check whether airplane mode is on. Airplane mode disables all wireless connections, including mobile data, and overrides the mobile data toggle. On an iPhone, swipe down from the top right corner to open Control Center and look for the airplane icon — if it is highlighted, tap it to turn airplane mode off. On Android, swipe down twice from the top to open Quick Settings and look for "Airplane Mode" — tap it to turn it off. After you turn off airplane mode, mobile data should work again.
If mobile data still will not turn on after restarting and disabling airplane mode, contact your carrier. They can check whether your account is active, whether there are any service outages in your area, and whether your SIM card is working properly. You can usually reach them by calling the number on the back of your carrier's bill or through their website.
Frequently Asked Questions
Does turning off mobile data stop me from getting calls and texts?
No. Calls and texts use a different part of your carrier's network and work even when mobile data is off. You will still receive calls and texts, and you can still make them. Only apps and services that need the internet — like email, maps, or web browsing — will not work without mobile data or Wi-Fi.
Will my phone use mobile data if I am connected to Wi-Fi?
Your phone will prefer Wi-Fi over mobile data when both are available. If you are connected to a Wi-Fi network, your phone will use that connection for internet instead of using mobile data. This is why turning mobile data off does not affect Wi-Fi — they are separate connections.
What is the difference between mobile data and a data plan?
Mobile data is the connection itself — the ability to use your carrier's network for the internet. A data plan is the amount of data your carrier allows you to use each month. If your plan includes 10 gigabytes per month, that is the limit on how much mobile data you can use before overage charges explore.
Can I use mobile data on a phone without a plan?
No. Mobile data requires an active plan with your carrier. If you have a phone but no active service, you can still use Wi-Fi, but you cannot use mobile data. You also cannot make calls or send texts without a plan, though you can call emergency services (911 in the US) even without service.
Why is my mobile data so slow?
Mobile data speed depends on your carrier's network, how many people are using it in your area, and how far you are from the nearest tower. If you are indoors or in a building with thick walls, the signal is weaker and slower. If you are in a crowded area during peak hours, the network may be congested. Moving to a window or outside usually improves speed. If it is consistently slow everywhere, contact your carrier to check for outages or network issues.