Updated: 2025-05-12 09:47:34
You just got off the plane and want to check the train schedule—but your phone has no internet. Has this ever happened to you? Maybe you were rushing before the trip and forgot to prepare, or you planned to use international roaming but changed your mind after seeing the price. Sometimes flight changes or unexpected layovers mess things up. And sometimes, you try connecting to the airport Wi-Fi, but nothing seems to work. Don’t panic—it's not too late to get an eSIM even after you arrive in Japan!
This happens to a lot of people, so there’s no need to feel embarrassed. With just a few simple steps, you can quickly get connected again. In this article, we’ll show you how to fix it fast, so you can get online and start your Japan adventure worry-free!
There are usually two types of situations: first, you simply forgot to buy a Japan SIM card or eSIM before leaving home; second, you thought you'd use roaming or free airport Wi-Fi, but then realized roaming costs a fortune, or the free Wi-Fi is slow and unstable—and you urgently need a connection.
First things first: stay calm! Most Japanese airports, like Narita, Kansai, and Haneda, offer free Wi-Fi in the arrival halls. Look for networks with names like “Free Wi-Fi” and connect. You might have to open your browser and agree to the terms or do a simple sign-in.
If the free airport Wi-Fi is too slow or crowded, head to a convenience store (like 7-Eleven or FamilyMart) or a coffee shop inside the airport—most of them offer free, more stable Wi-Fi. Once you have internet access, you can buy an eSIM online right away.
As long as your phone supports eSIM (iPhone XR or later, and most newer Android models), you can easily buy and activate one within minutes.
Of course, you could buy a physical SIM card at the airport or rent a pocket Wi-Fi device. You could even turn on international roaming. But be careful: buying a SIM or pocket Wi-Fi at the airport or using roaming usually costs way more than buying an eSIM online. Plus, airport shops have limited options, and if you end up choosing the wrong plan, it’s often non-refundable and might come bundled with unnecessary services.
A smarter move? Connect to the airport Wi-Fi, go to a site like CDJapan Rental, and order an eSIM online. You'll receive a QR code within minutes, and you can install it yourself. Pricing is clear, and there’s no need to talk to staff or deal with complicated contracts.
Many eSIM providers (like CDJapan Rental) offer instant delivery. As long as you have a Wi-Fi connection—even if it’s from the airport or borrowed briefly from someone—you can order and install your eSIM in just a few minutes.
The installation process is super easy: scan the QR code ➔ add a new mobile plan ➔ turn on data roaming ➔ connect to the internet. No complicated paperwork, no waiting—just a few taps and you’re good to go!
Buying a physical SIM card means you’ll need to swap out your existing SIM using a SIM pin, reset some settings, and deal with tiny parts—pretty annoying if you’re fresh off a flight and juggling luggage. With an eSIM, you just scan a QR code and install—no need to remove anything or worry about losing tiny cards.
Even better, if you lose a physical SIM, you’re out of luck. But with an eSIM, once installed, it stays safely on your phone for the whole trip.
Since you're already in Japan, it’s best to choose a Japan-only eSIM. CDJapan Rental, for example, uses the local docomo network, meaning you get the same speed and coverage as Japanese users—no international routing that can slow you down.
Avoid global roaming eSIMs that cover "the whole world"—they often have speed limits or may not even work in remote areas like countryside towns or hot spring resorts.
Also, make sure your phone is eSIM-compatible. Most recent iPhones, Samsung, and Pixel models are fine. Just watch out if you bought your phone in mainland China or have a carrier-locked device—it might not support eSIM. If your phone is compatible, setup is simple: scan the QR code, input the activation code, turn on mobile data—that's it. No tech wizardry needed.
If you're nervous about setting it up, you can download the installation guide ahead of time. CDJapan Rental’s guides are super clear with step-by-step instructions, so even first-timers won’t have a problem.
Once you purchase the eSIM, make sure you have a working internet connection to scan the QR code! If the airport Wi-Fi is shaky, move to a corner with better reception or head to a café. And a big tip: once the eSIM is installed, do not delete it unless absolutely necessary—most eSIMs cannot be reinstalled once removed!
Even if you buy it last minute, eSIM prices are very reasonable. For example, CDJapan Rental offers popular short-term plans like 30GB or 50GB, and heavy users can choose unlimited data plans too. These are way cheaper than international roaming, and you don’t have to worry about deposits or return deadlines like with pocket Wi-Fi rentals.
If you only need internet for a day or two, there are small data, short-term plans too—no waste. And if you’re staying longer, they also offer 90-day plans. Overall, buying an eSIM online is way more cost-effective than buying a SIM card at the airport or renting a pocket Wi-Fi.
If you run into issues installing or connecting, don’t worry. Contact customer support right away. CDJapan Rental offers English (and even Chinese) support—you just need to send an email explaining your problem, and they usually reply quickly to help you get connected.
Reminder: Once your eSIM is downloaded and installed, don’t delete it unless absolutely necessary. Most eSIMs cannot be reinstalled once deleted!
Even though you can fix the situation after landing, we still recommend buying your eSIM before your trip whenever possible.
That said, technology is amazing nowadays—if your phone supports eSIM, last-minute purchase and installation are totally doable. Choosing a reliable Japan-only eSIM provider means better speeds and service too. So even if you decide to hop over to Japan on a whim without internet prep, no worries! Grab a Japan eSIM, and you’ll be back online in just a few minutes.
CDJapan Rental offers flexible eSIM options—you can buy before your trip or even after you land. Orders placed just five minutes before use are totally fine, making it super convenient for spontaneous travelers!
Get Your Japan eSIM Now!
