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You’ve just landed in Tokyo after a long flight.
You want to check which train will take you to your hotel. You need Google Maps to find the station. Maybe you want to message someone to say you’ve arrived.
And then you realize: you don’t have mobile data yet.
Tokyo is an incredibly easy city to travel around once you can use your phone. Without it, even something as simple as finding the right station exit can suddenly become complicated.
That’s why mobile data is one of those things I’d sort out before leaving home.
Not because setting up an eSIM is exciting.
Because when you land in Tokyo, you want to open Google Maps and go.
Get your mobile data sorted before you fly
You can buy a physical SIM card after arriving in Japan, and there’s Wi-Fi at the airport.
But after a long flight, I personally wouldn’t want another thing to figure out before heading to my hotel.
An eSIM lets you set up your mobile data before your trip, without picking up or swapping a physical SIM card.
Do it at home while you have Wi-Fi, and that’s one less thing on your arrival-day list.
Why I chose Ubigi
There are lots of eSIM providers, and I don’t think everyone needs to use the same one.
But when I traveled to France, I used Ubigi myself.
My reasons were pretty simple: it was inexpensive, there were plenty of plans to choose from, and it was easy to use. Set it up, use it, forget about it — which is exactly what I want from an eSIM when I’m already juggling everything else about a trip.
Those are also the three things I’d care about when choosing an eSIM for a trip to Japan.
Why mobile data makes such a difference in Tokyo
If this is your first trip to Tokyo, you may be surprised by how often you reach for your phone.
Google Maps is especially useful here.
Tokyo’s train system is fantastic, but large stations can have many exits — and taking the wrong one can put you surprisingly far from where you wanted to be.
Then there are restaurant reservations, opening hours, translations, digital tickets and QR codes.
You don’t need to spend your trip thinking about mobile data.
You just need it to work when you need it.
That’s the real reason I’d arrange an eSIM before coming to Japan.
Ubigi’s Japan plans
Ubigi sells Japan-only data plans, so you’re not paying for coverage in countries you’re not visiting. Prices below are from Ubigi’s own site, checked in late September 2026:
| Data | Valid for | Price |
|---|---|---|
| 3GB | 15 days | US$7.50 |
| 10GB | 7 days | US$14 |
| 10GB | 30 days | US$16.50 |
There are larger and unlimited options too, worth a look if your trip is longer or you’ll be using more data — streaming, uploading photos, or working while you travel.
How much you actually need comes down to how you use your phone. Google Maps, train routes, restaurant searches and messaging use relatively little data. Streaming video or tethering a laptop will use a lot more. Check the current plans against how you expect to use your phone, rather than guessing at a fixed number.
In Japan, Ubigi’s plans run on the NTT Docomo and KDDI networks — two of the country’s main carriers.
Setting up before you fly
Before your trip, check that your phone supports eSIM and is unlocked, then buy your Japan plan. Ubigi emails you a QR code, which you scan to install the eSIM — do this at home, on Wi-Fi, so it’s already sitting on your phone before you leave.
You don’t need to activate it early, though. With Ubigi’s Smartstart, the plan’s validity period only starts once you actually arrive in Japan and connect, not the moment you install it. Just don’t leave it too long — a plan not activated within six months of purchase expires.
The goal is simple:
Haneda or Narita → phone on → mobile data → Google Maps → go.
Not:
Haneda or Narita → find Wi-Fi → figure out SIM cards → troubleshoot phone → finally leave the airport.
One thing to know before you buy
Ubigi is primarily a data eSIM.
That means you shouldn’t buy it expecting a Japanese phone number for standard calls and SMS.
For many visitors, that isn’t a problem. With mobile data, you can still use internet-based apps such as WhatsApp and FaceTime.
But if having a local Japanese phone number is important for your trip, a data-only eSIM may not be the right solution for you.
Quick Q&A
Does Ubigi give me a Japanese phone number?
No. It’s data only, so calls and texts go through apps like WhatsApp or FaceTime instead.
Can I use it as a hotspot for my laptop?
Yes — Ubigi’s Japan plans allow data sharing, so your phone can act as a hotspot. It just uses your data faster.
What if I run out of data?
You can top up directly in the Ubigi app, even without Wi-Fi or remaining data.
When does my plan actually start?
Not when you install it — with Smartstart, the countdown begins once you arrive in Japan and connect.
Is Ubigi a good eSIM for Japan?
I chose Ubigi for my own trip because it was inexpensive, flexible and easy to set up. And that’s exactly what I’d want from an eSIM when arriving in Tokyo.
The best part isn’t the eSIM itself. It’s landing in Tokyo, taking out your phone, opening Google Maps and heading straight into the city.
Set it up before you fly, and it’s one less thing to think about when you arrive.