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Three Mobile Data Not Working on Samsung Galaxy

TU
By TelecomUltra Editorial Team · Reviewed June 2026

Last updated: 24 July 2026 · Three · Samsung Galaxy

⏱️ Fix time: 5–15 min 🇬🇧 UK Guide Verified June 2026

What this means: Three Mobile Data Not Working on Samsung Galaxy means this feature is not working correctly. Follow the steps below to diagnose and fix the issue on your Samsung Galaxy with Three.

⚡ Quick Fix Summary — Mobile Data Not Working on Samsung Galaxy
  1. Confirm mobile data toggle is on
  2. Check APN settings are correct
  3. Toggle Airplane Mode to reset connection
  4. Restart device to clear network state

ℹ️ About Three — Mobile Data Not Working

Three operates on the Three (own network). Three's Feel At Home roaming covers 71 destinations. iD Mobile and SMARTY also use Three's network.

Known Samsung Galaxy considerations: 5G coverage mainly in city centres. eSIM supports dual-SIM on compatible devices.

Fix Three Mobile Data on Samsung Galaxy

1

Enable Mobile Data

Go to Settings → Connections → Mobile networks and confirm Mobile Data is on.

2

Toggle Airplane mode

Enable Airplane mode for 30 seconds then off — forces network re-registration.

3

Check APN

Go to Settings → Connections → Mobile networks → Access Point Names. Confirm APN is set to three.co.uk.

4

Restart device

Power off fully, wait 10 seconds, power on. Clears radio firmware errors.

5

Reinsert SIM

Remove, clean contacts, reinsert firmly — then power on.

6

Check network mode

Go to Settings → Connections → Mobile networks → Network mode — set to 4G/LTE preferred or 5G/4G Auto.

7

Reset network settings

Go to Settings → General management → Reset → Reset network settings. Re-enter APN after reset.

8

Contact Three

Call Three on 333 to check data provisioning on the SIM.

⚡ Three APN Settings Reference

SettingValue
APNthree.co.uk
Username(leave blank)
Password(leave blank)
MMSChttp://mms.um.three.co.uk:10021/mmsc
Three Support333

Frequently Asked Questions

What is the best way to fix Mobile Data Not Working on Samsung Galaxy?

Start by toggling Airplane mode, then restarting the device. If that doesn't work, check the APN at Settings → Connections → Mobile networks → Access Point Names — confirm it is set to three.co.uk. If still failing, reset network settings and contact Three on 333.

Do I need to contact Three to fix this?

Most Mobile Data Not Working issues on Samsung Galaxy can be resolved by following the steps above without contacting Three. If the problem persists after all steps, call Three on 333 — they can check for account-level or network-side issues.

Will a network reset help with Three on Samsung Galaxy?

Yes — a network reset at Settings → General management → Reset → Reset network settings clears corrupted APN settings and network configurations. Remember to note your Wi-Fi passwords first as they will be cleared. Re-enter the Three APN (value: three.co.uk) after the reset.

📞 When to Call Three

If all steps above have not resolved the issue, call Three on 333 (free from Three). Ask them to check data provisioning, account status, and any local network events.

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