During your trip to Japan, have you ever experienced, "Suddenly the connection speed became slow" or "Google Maps is taking a long time to load"?
Even when using eSIM, depending on the location, time of day, and surrounding communication environment, the connection speed may temporarily decrease.
In this article, we will explain in detail the places and causes where communication tends to slow down during travel, as well as measures to use it comfortably.
Main Places Where Communication Slows Down During Travel
In Japan, you can use mobile communication over a wide area, but in the following places, the connection speed may decrease.
| Location | Communication Status |
|---|---|
| Subway/Underground Stations | △ May become unstable deep underground |
| Long Tunnels | △ May temporarily be difficult to connect |
| Mountainous Areas | △ Connection speed may decrease depending on the area |
| Event Venues | △ Speed may decrease when many users are concentrated |
| Busy Times at Stations and Airports | △ Communication may become congested |
In these places, rather than completely losing communication, it is more common to see cases where the connection speed temporarily decreases.
Main Causes of Slow Communication Speed
The causes of decreased connection speed are mostly due to the surrounding communication environment, not the eSIM itself.
- Many users causing congestion on the line
- Weak signal in mountainous areas or underground
- Switching between base stations
- High-speed movement (such as on Shinkansen or express trains)
- Exhausted high-speed data allowance in the contract plan
In many cases, moving to a different location or reconnecting after some time can improve the situation.
Ways to Improve Communication Speed
- Move to a less crowded area
- Turn airplane mode ON and OFF to reconnect
- Restart your smartphone
- Check if there is remaining high-speed data
- Utilize Wi-Fi where available
Temporary decreases in connection speed can often be improved just by reconnecting. Start by trying the simple methods.
Points to Maintain Communication Speed During Travel
To maintain a comfortable communication environment during your trip to Japan, it is reassuring to keep the following points in mind.
- Choose a data plan that matches the number of travel days
- Complete eSIM setup before traveling
- Save Google Maps for offline use
- Download videos in advance while on Wi-Fi
- Reconnect after some time in crowded places
Connection speed is not always constant. In underground areas, mountainous regions, and event venues, the speed may temporarily decrease, but in many cases, it improves when the location or time changes.
Frequently Asked Questions
Does using eSIM cause slow communication speed?
No. The communication speed is determined not by the eSIM itself, but by the network of the service provider you are using and the surrounding communication environment. When using the same line, there is not much difference between physical SIM and eSIM.
Why did the communication speed suddenly slow down during my trip?
In places with many users, such as underground, mountainous areas, or tunnels, the communication speed may temporarily decrease. Also, if you exhaust your high-speed data allowance, speed restrictions may apply.
What should I do if the communication speed is slow?
Turning airplane mode ON and OFF, restarting your smartphone, or moving to a different location may improve the situation. It is also recommended to check if there is remaining high-speed data.
Will communication speed slow down in underground areas or on the Shinkansen?
In deep underground areas or long tunnels, communication may temporarily become unstable. However, in many cases, communication recovers in a short time.
How many GB should I have for peace of mind during my trip?
If you mainly use map apps and social media, 3-5GB is sufficient. For long-distance travel or frequent video viewing, 10GB or more is recommended. If you want to use data without worrying about limits, an unlimited plan is advisable.
Will using free Wi-Fi improve communication speed?
If the Wi-Fi at hotels or cafes is stable, it may improve the situation. However, public Wi-Fi may also slow down depending on congestion.
Is there anything I should prepare before my trip for peace of mind?
Setting up your eSIM before your trip and saving offline maps and information about hotels and tourist spots will provide reassurance, even if communication becomes temporarily unstable.
Conclusion
The causes of slow communication speed during travel are mostly due to the location, time of day, and communication environment, not the eSIM itself. Temporary decreases in speed are not uncommon, and knowing the appropriate measures will allow you to enjoy your trip with peace of mind.
- Communication speed may decrease in underground, mountainous areas, and tunnels
- Congestion may occur at busy stations and event venues
- Turning airplane mode ON and OFF or restarting may improve the situation
- Saving maps and necessary information before your trip is reassuring
- Choosing a data capacity that matches your travel style is important
By preparing your eSIM before your trip and knowing how to respond if communication slows down, you can comfortably use Google Maps, transit information, and tourist information during your trip to Japan.
