How to Fix iPhone Cellular Data Not Working

Cellular data not working on iPhone is usually caused by a disabled mobile network setting, weak carrier coverage, an outdated carrier profile, or a SIM issue. The fastest fixes are to confirm cellular data is enabled, toggle Airplane Mode, restart iPhone, check carrier settings, and reset network settings if no data connection continues.

Steps

Open Settings > Cellular and confirm Cellular Data is turned on. If mobile data is off, enable it and check whether the affected app is also allowed to use cellular data.
Turn Airplane Mode on for 10 seconds, then turn it off. This forces iPhone to reconnect to the carrier network and often restores a no data connection.
Restart iPhone and check the signal indicator. Poor or no coverage can make cellular data not working appear like a device problem when the issue is actually network-related.
Open Settings > General > About and wait for any Carrier Settings Update prompt. Install the update if available, because outdated carrier settings can block mobile data access.
Go to Settings > General > Transfer or Reset iPhone > Reset > Reset Network Settings. This clears saved network configurations and can fix persistent mobile data off errors, APN issues, or failed reconnection.

Common Issues and Fixes

Issue: Cellular Data toggle is on, but no data connection remains. Likely cause: temporary network registration failure. Fix: toggle Airplane Mode, restart iPhone, and recheck signal strength.
Issue: Only one app fails on mobile data. Likely cause: app-level cellular access is disabled. Fix: open Settings > Cellular and enable data access for the specific app.
Issue: Data stopped working after iOS update or SIM swap. Likely cause: outdated carrier settings or SIM authentication problem. Fix: update carrier settings, remove and reinsert the SIM, or test another SIM if available.
Issue: 5G or LTE appears, but pages do not load. Likely cause: weak local coverage or carrier outage. Fix: switch between 5G Auto, LTE, or 4G in Voice & Data, then test again in another location.
Issue: Cellular data not working abroad. Likely cause: roaming disabled or plan does not include roaming data. Fix: enable Data Roaming only if the carrier plan supports it.

Option	Best For	Limitation
Airplane Mode toggle	Fast reconnect	May not fix SIM or carrier issues
Restart iPhone	Minor system glitches	Temporary if network problem remains
Carrier settings update	Post-update or SIM issues	Update may not always be available
Reset Network Settings	Persistent no data connection	Removes saved Wi-Fi passwords

Quick Tips

Dual SIM models can have cellular data assigned to the wrong line. Check the selected line under Cellular Data.
Some carriers disable data after plan limits are reached. Account status and data balance may need verification.
VPN profiles can block mobile internet on some networks. Disable VPN temporarily and test again.
If calls and texts also fail, the problem is more likely SIM-related or carrier-related than app-related.

Why does iPhone say LTE or 5G but internet still does not work?

The status icon only shows network attachment, not guaranteed internet access. Carrier outages, APN errors, or blocked data service can still prevent loading.

When is a carrier contact necessary?

Carrier support is necessary if no data connection continues after network reset, if SIM is not detected, or if the account has a service restriction.