Why Is My eSIM Not Working in Japan? (Quick Fix Guide)
If your eSIM isnβt working in Japan, donβt worry β this is a common issue travelers experience after landing.
Many users ask:
Why does my eSIM not work in Japan?
- π In most cases, the problem is caused by network compatibility, settings, or automatic network selection.
The good news: Most issues can be fixed in under 2 minutes.
In this guide youβll learn:
- The most common causes in Japan
- Quick fixes
- Japan-specific network tips
- How to restore connection instantly
Most common reason in Japan: network compatibility
Japan uses specific LTE and 5G frequency bands that not all international phones support.
Main carriers in Japan:
- NTT Docomo
- SoftBank
- KDDI (au)
Some phones connect better to certain networks than others.
Compatibility guide: π https://novesim.com/compatible-devices/Β
Automatic network selection chose the wrong carrier
Phones often connect automatically to the first available network β not the best one.
Fix:
- 1. Open network settings
- 2. Turn off automatic selection
- 3. Choose another network manually
- 4. Test connection
Often switching networks solves the issue instantly.
Roaming is disabled
Many travelers assume roaming should be off abroad β but for travel eSIMs it must be enabled.
- Fix: Settings β Cellular β eSIM β Data Roaming β ON
Roaming guide: π https://novesim.com/do-you-need-roaming-for-esim/
eSIM installed but not activated yet
- If you installed your eSIM before departure, it may not activate until it detects a supported Japanese network.
This is normal behavior. Activation timing guide: π https://novesim.com/does-esim-work-immediately-after-landing/
Wrong SIM selected for data
Sometimes the phone is still using your primary SIM for data.
- Check: Settings β Mobile Data β Data Line β select eSIM
Switching guide: π https://novesim.com/how-to-switch-between-esim-and-physical-sim-while-traveling/
APN settings failed to load
Rare but possible.
Symptoms:
- Signal bars visible
- No internet connection
Fix:
- Restart device
- Toggle airplane mode
- Reinstall profile if needed
- Ask for APN settings
Your phone supports eSIM β but not Japanese bands
- Important distinction: eSIM compatibility β full network compatibility
Some phones support eSIM but lack frequency support for Japanese networks. This is more common with:
- Older devices
- Region-locked phones
- Imported models
Data plan expired or used up
If your plan is finished, your phone may still show signal but internet wonβt work.
Check whether you received usage alerts:
- Activation notification
- 50% data used
- 80% data used
- Data exhausted
- Expiry reminder
Usage guide: π https://novesim.com/what-happens-when-your-esim-data-runs-out/
Quick fix checklist
Try these steps in order:
- Enable roaming
- Restart phone
- Toggle airplane mode
- Switch network manually
- Confirm data line = eSIM
- Check remaining data
Most travelers fix the issue immediately.
Japan-specific tip
In Japan:
- Docomo usually offers the widest coverage
- SoftBank works best in cities
- KDDI may be weaker for foreign devices
If one network fails, try another manually.
When to contact support
Contact support if:
- No networks appear
- Activation failed
- QR installation failed
- Profile missing
These cases are rare and usually require reprovisioning.
Biggest misconception
- Myth -> eSIM doesnβt work in Japan.
- Reality -> eSIM works in Japan β most issues are device compatibility or settings.
Real traveler scenario
- Traveler lands in Tokyo.
- Phone shows signal but no internet.
- They switch network from KDDI β Docomo.
- Connection works instantly.
Final verdict
If your eSIM isnβt working in Japan, the cause is usually:
- Incompatible frequency bands
- Wrong network selection
- Roaming disabled
- Incorrect data line
Most problems can be fixed quickly from settings.
Find compatible plans for Japan: π https://novesim.com/destinations/
Frequently asked questions
Why is my eSIM not working in Japan?
Usually because of network compatibility, wrong carrier selection, or roaming disabled.
Does eSIM work in Japan?
Yes. Most travel eSIM plans support Japanese networks.
Which network is best in Japan?
Docomo often provides the widest coverage.
Why do I have signal but no internet?
This usually means your phone connected to a weak or unsupported network.

