iOS 26.1 Cellular Data Not Working? Here’s How to Fix It.

You updated to iOS 26.1, and now your iPhone says “No Service” or your mobile data is slow and keeps dropping. It’s frustrating, and you’re not the only one. Cellular problems after a big iOS update usually come from a software glitch, outdated carrier settings, or a network configuration conflict, and most of them can be fixed at home.

Before you call your carrier or book an Apple Store visit, work through the steps below in order.

Start With These Quick Fixes (60 Seconds)

These simple steps solve the problem more often than you’d expect.

Check that Cellular Data is on. Go to Settings > Cellular and make sure Cellular Data is switched on.
Toggle Airplane Mode. Turn it on for about 20 seconds, then turn it off. This forces your iPhone to reconnect to the network.
Restart your iPhone. A reboot clears temporary software glitches.

Step-by-Step Solutions

If the quick fixes didn’t work, go through these in order.

1. Rule Out Wi-Fi Problems

A weak Wi-Fi connection can make it seem like your cellular data is broken.

Turn off Wi-Fi from Control Center and try loading a web page. If it loads, your cellular data is working. You can also turn on Wi-Fi Assist (Settings > Cellular > Wi-Fi Assist) so your iPhone switches to cellular when Wi-Fi is poor.

2. Check for a Carrier Settings Update

Carriers release small updates that help your iPhone connect properly to their network.

Go to Settings > General > About. If an update is available, a pop-up appears. Stay on that screen for 15 to 20 seconds and tap Update if you see the prompt.

3. Switch From 5G to LTE

In some areas 5G is patchy, and a stable LTE connection works better.

Go to Settings > Cellular > Cellular Data Options > Voice & Data.
Change 5G Auto to LTE.
Test your connection.

You can switch back to 5G later once things are stable.

4. Reinsert or Refresh Your SIM

Physical SIM:

Turn off your iPhone.
Use a SIM ejector tool to remove the SIM tray.
Check the SIM for dust, then put it back in.

eSIM:
If you use an eSIM, you can remove and add it again.

Go to Settings > Cellular and tap your plan.
Select Remove Cellular Plan.
Scan your carrier’s QR code again or use your carrier’s app to set it up.

Before you remove an eSIM, make sure you can get a new activation QR code or have your account details ready. In some cases, you’ll need to ask your carrier to issue a new one.

5. Reset Network Settings

This is one of the most effective fixes for stubborn cellular problems.

Go to Settings > General > Transfer or Reset iPhone > Reset.
Tap Reset Network Settings.
Your iPhone will restart.

Note: This erases saved Wi-Fi passwords, Bluetooth pairings, and VPN settings. You’ll need to rejoin your Wi-Fi networks and pair your Bluetooth devices again.

6. Check for VPNs and Configuration Profiles

VPNs, ad blockers, and configuration profiles can interfere with your data connection.

Go to Settings > General > VPN & Device Management.
Temporarily turn off any VPN, or remove any profile you don’t recognize or trust.

7. Update iOS Again

Apple often follows a major release with smaller fixes. Go to Settings > General > Software Update and install any update that’s available.

Still Not Working? Contact Your Carrier

If you’ve tried everything and the problem remains, the issue may be on your carrier’s side. Ask them to check:

Your account status and any billing problems
Network outages in your area
Whether your line is set up correctly (especially for 5G and VoLTE)

Quick Reference: Which Fix for Which Problem?

Problem	Try This
“No Service” or a sudden drop	Airplane Mode toggle, restart, carrier settings update
5G is slow or unreliable	Switch to LTE in Cellular Data Options
Data works on and off	Reset Network Settings
Nothing works	Contact your carrier about account or line issues

Frequently Asked Questions

Why does my iPhone say “No Service” after an iOS update?
Usually it’s a temporary software glitch, outdated carrier settings, or a network configuration conflict. Restarting your iPhone and checking for a carrier update fixes it in many cases.

Will resetting network settings delete my data?
It doesn’t delete your photos, apps, or messages. It does erase saved Wi-Fi passwords, Bluetooth pairings, and VPN settings.

Should I switch to LTE permanently?
No. It’s a useful test and a temporary workaround if 5G is unstable where you are. Switch back to 5G Auto when the connection is reliable again.

Is it safe to remove my eSIM?
It’s safe if you can add it again afterward. Have your carrier’s QR code or app ready first, because some carriers need to reissue the eSIM.

How do I know if the problem is my iPhone or my carrier?
Try your SIM in another phone, or a different SIM in your iPhone. If the problem follows the SIM, contact your carrier. If it stays with the iPhone, the fault is on the device.

Final Thoughts

Most cellular problems after an iOS update can be fixed with a restart, a carrier settings update, or a network reset. Work through the steps in order, and contact your carrier if the issue is still there at the end.