Convenient for Travel in Japan! Complete eSIM Guide: FAQs
Updated : 2025-06-05 18:59:00
For foreign travelers visiting Japan, having a way to connect your smartphone is very important. One of the most convenient options is an "eSIM." This article provides clear answers in a Q&A format to help first-time users feel confident using an eSIM. Be sure to check it out before your trip to Japan!
eSIM Basics
Q. What is an eSIM?
A. An eSIM is a digital SIM card built into your smartphone or tablet. You don’t need to swap a physical SIM card—just scan a QR code and you're connected.
Q. Where can I buy an eSIM?
A. You can buy one from online eSIM providers. It’s very convenient since you don’t need to spend time looking for a SIM card or renting a Pocket Wi-Fi after arriving at a Japanese airport.
Q. Can I buy an eSIM at the airport?
A. eSIMs are available at Japanese airports, but it’s better to buy online. eSIM Japan
Q. What are the requirements to use an eSIM in Japan?
A. Your smartphone must support eSIM and be unlocked. Compatible models include iPhone XR or later, Google Pixel series, and some Samsung Galaxy models. You can check compatibility below.
How to Quickly Check if Your Smartphone Can Use a Japanese eSIM in 5 Seconds
How to Use an eSIM & Important Notes
Q. How do I install an eSIM?
A. You can install it by scanning the QR code sent after purchase from your phone’s settings. Wi-Fi is needed, so make sure you have internet access ready. Many travelers buy and set up their eSIM while waiting at immigration after arriving in Japan. eSIM Japan
Q. Can I use it right after installing?
A. For example, with Travel Mobile eSIM, you activate it from your My Page. After activation, you can connect to the network. So install the eSIM and then you'll be able to use it.
Q. How many devices can use one eSIM?
A. One eSIM profile can only be used on one device. To use it on another device, you’ll need to buy it again.
Q. What if I lose or reset my phone?
A. Since the eSIM is tied to your device, it needs to be reissued. Contact your provider.
Q. What if I delete the eSIM?
A. In many cases, once deleted, it cannot be reinstalled. Please avoid deleting it.
Connectivity and Features
Q. Can I use it anywhere in Japan?
A. If the eSIM uses networks like docomo, SoftBank, or au, it can be used nationwide. Rakuten Mobile may have unstable connections in some areas. Travel Mobile eSIM uses the network of docomo, Japan’s largest carrier, so it works well in both cities and rural areas.
Q. Is the connection fast?
A. Yes, eSIMs using local Japanese networks offer fast and stable connections.
Q. What's the difference between a local eSIM and a roaming eSIM?
A. Local eSIMs connect directly to Japanese networks, so they are faster and more stable. Roaming eSIMs use foreign networks and may have slower speeds or unstable connections. Also, some Japanese web services may not work. It's best to buy a Japanese eSIM from a Japanese provider for use in Japan.
Q. Can I use tethering?
A. Most eSIMs for Japan support tethering. Check your "Internet Sharing" settings on iPhone or Android. For iPhones, you may need to configure the APN settings to use tethering.
Q. What if tethering doesn’t work?
A. While most eSIMs for Japan support tethering, your home country's mobile plan may not allow it. Even if the Japanese eSIM supports it, you may need to ask your provider at home to enable tethering on your phone.
Q. Can I check how much data I have left?
A. With Travel Mobile, you can log in to My Page to check your data usage and remaining days.
Q. Is an eSIM safer than public Wi-Fi?
A. Yes. eSIMs use carrier networks, which are safer and more stable than public Wi-Fi.
Apps and Services You Can Use
Q. Can I use LINE or WhatsApp?
A. Yes. As long as phone number verification is complete, you can use them with just data.
Q. Does it include a phone number?
A. Travel eSIMs are for data only, so no phone number is included. Use apps like LINE for calls.
Q. Can I make emergency calls in Japan?
A. You can’t make emergency calls with a data-only eSIM. Use a SIM with voice service or a public phone if needed.
Plans and Contracts
Q. How long is the plan valid?
A. Most are pay-as-you-go plans valid for a certain number of days from activation. Check the start and end dates in advance.
Q. Can I carry over unused data?
A. No, data from one-time-use plans cannot be carried over.
Q. Can I share an eSIM?
A. No. For security and technical reasons, one eSIM can only be used on one device.
Support and Troubleshooting
Q. I can’t scan the QR code
A. Some camera apps may fail to scan it. If that happens, manually enter the setup info. Just copy and paste the information—it’s simple.
Q. Can I install the eSIM more than once?
A. eSIMs sold for tourists visiting Japan can only be installed once per device.
Q. Is support available?
A. Many eSIM providers offer support via email or chat in English. That said, it's best if you don’t need support at all. Before buying an eSIM, make sure your smartphone is unlocked and supports eSIM.
Q. Do I need to pick anything up at the airport?
A. No. Since everything is done online, you can use your eSIM as soon as you arrive at the airport.
Important Notes
Q. Credit card payment authentication errors
A. Many eSIMs offered by Japanese companies require credit card payments. After arriving in Japan, some users are unable to complete the purchase due to 3D Secure authentication failures. Make sure your credit card can be authenticated via email in advance.
eSIMs are a smart and convenient way to stay connected while traveling in Japan. Use this guide to find the right eSIM for you and enjoy your trip!