Your mobile data usually stops working for a simple reason: it's turned off, your phone is using the wrong SIM line, you've used up your data, there's no coverage or an outage, or data roaming is off while you're abroad. Sometimes a settings glitch is the cause, and a quick restart fixes it. This guide walks you through the checks in order, on iPhone and Android, at home and abroad. Most of them take less than a minute.
Why is my mobile data not working?
When you have no data, or data shows as on but nothing loads, it's usually one of these:
- Mobile data is off: for the whole phone, for the line you're using, or for one app.
- Airplane Mode is on, or your phone hasn't reconnected properly after it.
- You've used up your data, or your bundle or top-up has expired.
- Your "unlimited" plan has slowed down after a fair use limit, or doesn't cover what you're doing (like hotspot or roaming).
- Weak coverage or a network outage where you are.
- The wrong line is set for data on a phone with two SIMs or eSIMs.
- Data roaming is off when you're in another country.
- Wrong network settings: an incorrect APN, an old carrier settings file or outdated software.
- A problem with your SIM or account: a damaged SIM, a line that isn't active yet, or an unpaid bill.
Quick fixes to try first
Try these in order. After each one, turn Wi-Fi off and open a web page to test your mobile data.
- Check that mobile data is on. Open Control Center on iPhone or the quick settings panel on Android and make sure the mobile data icon is on. If it's already on, turn it off and back on.
- Turn Airplane Mode on, then off. Apple suggests leaving it on for at least 15 seconds (Apple: If you see SOS, No Service, or Searching).
- Restart your phone. It sounds too simple, but it often clears the problem.
- Look at the top of your screen. With Wi-Fi off, you should see signal bars and a network label like 4G, LTE or 5G. Google says that if you see no label, you may be in an area without coverage, so move somewhere else or step outside (Android Help: Fix internet connection problems).
- Check how much data you have left in your carrier's app or account.
- Take out your SIM card and put it back in (physical SIM only). Turn your phone off first, check the SIM and tray for damage, then restart.
Still no data? Go to the steps for your phone below. Other phone problems? See 20 common mobile phone problems and their solutions.
How to fix mobile data on iPhone
Depending on your region and iOS version, the menu is called Cellular, Mobile Data or Mobile Service. The steps are the same.
1. Turn on cellular data and the right line
Go to Settings > Cellular and turn on Cellular Data. If you have two lines, tap each one and check it's on. If a line is off, tap Turn On This Line. Then tap Cellular Data and choose the line you want to use for data (Apple: Use cellular data on your iPhone or iPad).
2. Check that the app is allowed to use data
If only one app has no data, scroll down in Settings > Cellular. Each app has its own switch. An app with the switch off only works on Wi-Fi.
3. Update iOS and your carrier settings
Go to Settings > General > Software Update and install any update. Then connect to Wi-Fi and go to Settings > General > About. If a carrier settings update is available, you'll see a message to install it (Apple: Manually update carrier settings).
4. Reset network settings
Go to Settings > General > Transfer or Reset iPhone > Reset > Reset Network Settings. This removes saved Wi-Fi networks and VPN settings, and Apple says it may also turn data roaming off, so check it again if you're abroad. Don't tap Delete All eSIMs, which is a separate option in the same menu (Apple: Reset iPhone settings to their defaults).
Seeing "Could Not Activate Cellular Data Network"? Here's how to fix that error.
How to fix mobile data on Android (Samsung and Pixel)
Menu names change a little between models and Android versions.
Samsung Galaxy
- Go to Settings > Connections > Data usage and turn on Mobile data.
- Go to Settings > Connections > Mobile networks. Check Network mode is set to an option that includes 5G or LTE, if your plan supports it. Abroad, also check Data roaming here.
- If it still doesn't work, reset your network settings. Go to Settings > General management > Reset and tap Reset mobile network settings (called Reset network settings on some models) (Samsung: How to troubleshoot mobile data issues).
Google Pixel
- Go to Settings > Network & internet > SIMs and make sure Mobile data is on. Tap your carrier and check Use SIM is on.
- Tap your carrier again and check the preferred network type. Battery Saver turns off 5G, so turn it off if you expect 5G.
- Reset your mobile network settings in Settings > System > Reset options > Reset mobile network settings (Pixel Phone Help: Fix mobile connectivity issues).
Check the APN
The APN tells your phone how to connect to your carrier's data network. If it's wrong, you can have full signal and still no data. On Android, you'll find it under the mobile network settings, with an option to reset it to default. Only change it with the values your carrier gives you. More in what is an APN and how to change it.
Why is my unlimited data not working?
An unlimited plan can still stop or slow down. Check these:
- Fair use or "priority" data: many unlimited plans give you a set amount of high-speed or priority data each month. After that, your speed can drop, especially when the network is busy. Your plan's terms show the limit. More in do unlimited data plans without throttling exist.
- Hotspot data: sharing your connection often has its own, smaller allowance.
- Roaming data: "unlimited" at home rarely means unlimited abroad. In the EU, for example, operators can set a fair use limit on unlimited plans when you roam (Your Europe: Roaming in the EU).
- Your account: an unpaid bill, an expired plan or a block on your line can stop data. Check your carrier's app.
To see your usage, here's how to check data usage on iPhone and on Android.
No data after a new SIM, eSIM or phone?
A new line isn't always ready right away. If you've just changed SIM, phone or carrier:
- Give it time and restart. A new line or a number transfer has to be finished on your carrier's side. Ask your carrier how long it takes.
- Update your carrier settings on iPhone (see above). Apple says to download the carrier settings for a new carrier after you put in a new SIM.
- Check the APN if your phone came from another carrier.
- Check your phone is unlocked if your new SIM is from a different carrier than the one that sold you the phone.
Using an eSIM? It has its own checks, like turning the eSIM line on and choosing it for data. See eSIM not working? 9 ways to fix it.
Mobile data not working abroad?
Abroad, your phone needs a few more settings to be right:
- Turn on data roaming for the line you use for data. On iPhone, go to Settings > Cellular > Cellular Data Options > Data Roaming. With two lines, tap the line first (Apple). On Samsung, go to Settings > Connections > Mobile networks > Data roaming (Samsung: Turn data roaming on or off).
- Choose the right line for data. If you use a travel eSIM, set it as your data line and turn data roaming off on your home SIM to avoid charges. See the correct roaming settings for an eSIM.
- Check that roaming is included in your plan, or that you've added a roaming pass. Some plans block data abroad until you turn roaming on in your account.
- Select a network manually if your phone shows signal but no data. Try another local network in your network selection settings.
- Toggle Airplane Mode after you land so your phone connects to a local network.
If roaming is expensive or not included in your plan, a travel eSIM gives you local data without touching your home SIM. You install it before you leave and switch it on when you land. These SimOptions plans are data-only, so you keep your usual number on your home SIM for calls and texts.
Europe, USA and Asia plans shown · data-only eSIMs, no phone number · Find the eSIM for your destination
Is it your phone or the network?
If nothing above works, find out where the problem is:
- Check for an outage: look at your carrier's network status page, app or social media accounts. If others nearby have the same problem, it's on their side and you'll have to wait.
- Check the coverage map on your carrier's website for where you are. Weak signal? See how to improve cell phone reception.
- Run a speed test with Wi-Fi off. If it's very slow or fails, the connection is the problem, even if your phone shows signal.
- Try your SIM in another phone, or another SIM in your phone. If the other SIM works, ask your carrier for a new SIM.
- Contact your carrier. Apple suggests asking them to check that your account is active, that there's no outage, and that your phone isn't blocked. If they find nothing wrong, it may be a hardware problem, and the phone maker's support is the next step.
FAQs
Why is my data on but not working?
Your phone may have signal but no data connection. Toggle Airplane Mode, restart, and check the right line is chosen for data. If that doesn't help, update your carrier settings, check the APN and reset your network settings.
Why did my mobile data suddenly stop working?
Common reasons are: you ran out of data, your plan expired, there's an outage, or a setting changed after an update. Check your data balance and your carrier's network status first, then try the quick fixes above.
Why do I have no data even though I have signal bars?
Signal bars only show you're connected to the network for calls and texts. Data can still be off for that line, blocked by a wrong APN, or limited by your plan. On a phone with two SIMs, the other line may be the one set for data.
How do I know if I've run out of data?
Check your carrier's app or account, which shows what's left. Many carriers also send a text when you're close to your limit. Your phone's own counter shows usage, not what's left in your plan.
Why is my unlimited data not working?
Your plan may have slowed you down after a fair use limit, your hotspot or roaming allowance may be used up, or there's a problem with your account. Check your plan's terms and your carrier's app.
Does resetting network settings delete my eSIM?
On iPhone, Reset Network Settings and Delete All eSIMs are two separate options, so pick only the first. If you're unsure, ask your carrier or eSIM provider before you reset. More in our eSIM fixes guide.
Why is my mobile data not working abroad?
Usually data roaming is off for the line you use for data, roaming isn't included in your plan, or your phone is using the wrong line. Turn on data roaming for that line and choose it for mobile data.
