Why Is My eSIM Not Working in Vietnam? (Quick Fix Guide)
If your eSIM isn’t working in Vietnam, don’t worry — this is a common situation travelers may experience after arrival.
You might notice:
- Signal but no internet
- Slow connection
- No network
and ask: Why is my eSIM not working in Vietnam?
- 👉 In most cases, the problem is caused by network selection, roaming settings, or device compatibility.
Most issues can be fixed within minutes.
Most common reason: wrong network selected
Vietnam has several mobile carriers:
- Viettel
- Vinaphone
- Mobifone
Your phone may automatically connect to a weaker network.
Fix
- 1. Go to Network Selection
- 2. Turn off automatic mode
- 3. Choose another carrier manually
- 4. Test connection
Switching networks often resolves the issue immediately.
Roaming is turned off
Travel eSIM profiles require roaming enabled abroad.
- Fix: Settings → Mobile Data → eSIM → Data Roaming → ON
eSIM installed but not activated yet
- If you installed your eSIM before departure, activation may occur only after it detects a supported Vietnamese network.
This is normal behavior. Activation guide: 👉 https://novesim.com/does-esim-work-immediately-after-landing/
Wrong SIM selected for data
Your phone might still be using your physical SIM for mobile data.
- Check: Settings → Mobile Data → Data Line → select eSIM
Switching guide: 👉 https://novesim.com/how-to-switch-between-esim-and-physical-sim-while-traveling/
Device compatibility issue
Some phones support eSIM but not all Vietnamese network bands.
Compatibility guide: 👉 https://novesim.com/which-phones-support-esim-in-2026/
More common with:
- Older devices
- Imported phones
- Region-locked models
APN settings didn’t load
Rare but possible.
Symptoms:
- Signal bars visible
- Internet not working
Fix:
- Restart device
- Toggle airplane mode
- Reinstall eSIM profile
- Ask for APN settings
Data plan expired or used up
Your phone may still show signal even if your plan has finished.
Check alerts:
- Activation notification
- 50% usage
- 80% usage
- Data exhausted
- Expiry reminder
Guide: 👉 https://novesim.com/what-happens-when-your-esim-data-runs-out/
Quick fix checklist
Try these steps:
- Enable roaming
- Restart phone
- Toggle airplane mode
- Switch network manually
- Confirm eSIM is data line
- Check remaining data
Most users resolve the issue quickly.
Vietnam-specific tip
In Vietnam:
- Viettel usually provides the strongest nationwide coverage
- Vinaphone works well in cities
- Mobifone may be weaker in rural areas
If connection is unstable, manually switching networks often helps.
When to contact support
Contact support if:
- No networks appear
- Installation fails
- Profile missing
- activation error
These are rare cases and usually require reprovisioning.
Biggest misconception
- Myth -> eSIM doesn’t work in Vietnam.
- Reality -> eSIM works in Vietnam — most issues are settings or network selection related.
Real traveler scenario
- Traveler lands in Hanoi.
- Phone shows signal but no internet.
- They switch network from Mobifone → Viettel.
- Connection works instantly.
Final verdict
If your eSIM isn’t working in Vietnam, it’s usually caused by:
- Wrong network selection
- Roaming disabled
- Incorrect data SIM
- Compatibility issue
Most problems can be fixed quickly from settings.
Check compatible plans for Vietnam: 👉 https://novesim.com/destinations/
Frequently asked questions
Why is my eSIM not working in Vietnam?
Usually because of wrong network selection, roaming disabled, or compatibility issues.
Does eSIM work in Vietnam?
Yes. Most travel eSIM plans support Vietnamese networks.
Which network works best in Vietnam?
Viettel often provides the strongest nationwide coverage.
Why do I have signal but no internet?
This usually means your device connected to a weak or unsupported network.

