![[Beginner-Friendly] What Is an eSIM? Do I Need One for My Trip to Japan?](/img/blog/74.jpg)
Updated: 2025-06-11 18:15:01
Some people who aren’t tech-savvy might genuinely ask: What’s an eSIM? I’ve never heard of it!
An eSIM is a virtual SIM card embedded inside your phone. Unlike traditional physical SIM cards that need to be inserted, you don’t have to swap or handle any cards—just scan a QR code and you’ll be connected to the internet in Japan. It’s perfect for independent travelers.
Many modern phones now support eSIM, such as iPhone XS and later, Google Pixel, Samsung Galaxy S series, etc. You can purchase an eSIM before your trip and go online as soon as you land in Japan—no lines, no shipping, no airport SIM pickup counters. Super convenient.
Please note that some phones from certain countries/regions may not support eSIM. Be sure to check whether your device is eSIM-compatible before buying. How to check if your phone supports eSIM
Physical SIM cards require you to open your SIM slot and replace your existing card. There’s also a risk of losing your original SIM card. Switching back and forth during your trip can be annoying.
Pocket WiFi means renting a separate device that you need to carry, charge, and make sure you don’t lose. It takes up space and sometimes has unstable signal quality.
eSIM, on the other hand, takes up no space, works once installed, and doesn’t require waiting in line, returning any devices, or worrying about loss. For light-packers and solo travelers, it’s the easiest and most efficient internet solution for Japan.
| Feature | eSIM | Pocket WiFi | Physical SIM |
|---|---|---|---|
| Portability | No extra device needed | Need to carry extra device | Just swap SIM card |
| Setup | Scan QR code | Turn on and connect | Insert and replace SIM |
| Risk | No loss risk | Easy to lose / forget to return | Card may be lost |
| How to get it | Online setup | Pick up at airport | Buy locally or via shipping |
Take U.S. travelers as an example: if you rely on international roaming with AT&T or Verizon, it may cost you over $10 USD per day. A five-day trip could cost more than $50—definitely not ideal if you're on a budget.
Physical SIMs are sold at airports, but they’re often more expensive, with long lines and compatibility issues. If you need internet immediately after landing to look up directions or your hotel, waiting in line can be really stressful.
The biggest advantage of eSIMs is: you can buy them before your trip and activate them upon arrival. No need to hunt for Wi-Fi or wait for shipping—just power on your phone and go online. Perfect for independent travelers.
A lot of people feel nervous when they hear “eSIM” for the first time—but it’s actually easy. In most cases, you just need to scan a QR code. If you know how to scan a code with your phone, you can set up an eSIM.
CDJapan Rental’s eSIMs come with full setup instructions in English and Chinese. The process is simple and beginner-friendly.
If you plan to rely solely on your current phone plan while roaming, the cost can add up quickly—$10+ per day is no joke. Plus, roaming speeds can be limited or unstable.
eSIMs offer much better value. CDJapan Rental provides unlimited data options, fixed data plans like 30GB or even 135GB, all at much more affordable prices. Plus, they use Japan’s local Docomo network, so you don’t need roaming enabled to stay connected—even in rural areas or on bullet trains.
If you plan to use Google Maps, message on LINE, scroll Instagram, or stream videos, and don’t want to deal with swapping SIM cards or carrying extra gear, an eSIM is pretty much the only choice.
A: If you're using a CDJapan Rental unlimited plan that charges by number of days, the plan won't start until you actually tap “activate.” You can scan the QR code and install it ahead of time, then activate it when you arrive in Japan. Just don’t tap activate early—once activated, the countdown begins, even if you’re not using data yet.
A: First, don’t delete the eSIM! Most issues can be solved with simple troubleshooting. We recommend contacting customer support from your provider—for example, CDJapan Rental offers installation guides and support. If you delete the eSIM, you might not be able to redownload it, and then it won’t work anymore.
A: Check your phone model to see if it supports eSIM. If not, we recommend using Pocket WiFi or a physical SIM card instead.
You don’t have to be a tech geek or know how to take apart your phone. If you can scan a QR code, you can set up an eSIM.
For travelers who want to save money and stay online throughout their trip in Japan, eSIMs are the most convenient and cost-effective option. We especially recommend getting a Japanese-based eSIM (like CDJapan Rental’s Docomo-backed plans)—compared to global eSIMs purchased outside Japan, local ones are cheaper, more reliable, and avoid compatibility problems.
Just make sure to buy it before your trip and activate it once you land—then you’ll be connected the moment you arrive, no stress.
Buy online in advance, get connected the moment you land—no lines, no Wi-Fi hunting, no SIM delivery delays!
View Japan eSIM Plans
