Rated 5 out of 5
Très facile à obtenir
« Acheter une esim en un clic, Très utile pour vos voyages au Japon et facile a utiliser »
Yoann Poaka
Japan eSIM
Japan eSIM on the NTT docomo network
NTT docomo 5G networkIs my phone compatible?
Your Japan eSIM, from €1.20, runs on NTT docomo’s 5G network, with a real Japanese IP address. Pick your plan, get your QR code straight away, and if you run low on data along the way, top up in the app.
Buy it whenever you like
Your plan starts when you first connect in Japan, not when you buy it. So you can get it days before you fly.
With every plan
- The NTT docomo network, in 5G where it’s available.
- A real Japanese IP address, just like a local line.
- Installs in 1 minute, and your QR code arrives straight away.
- Hotspot allowed: share your data with a laptop or a friend’s phone.
- Top up from the app or your account on the website.
- A real person on WhatsApp, 24/7, in English and French.
Calculator
Which plan for your trip length?
A week, 10 days, two weeks or a month: tell the calculator how long you’re staying and what you use your phone for. It estimates the data you need and suggests the plan that’s enough.
You’ll need about
7.7 GB
7.7 GB of 10 GBYou’ll have 2.3 GB left
Suggested plan10 GB · 30 days
€8.60
A rough estimate. You can top up from the app at any time.
Your plan’s validity needs to cover your whole stay, and it starts when you first connect in Japan. Running low on data halfway through your trip? Top up from the app or your account on the website.
Not sure what you use at home? Our guide explains how much data you need on a trip to Japan. And if you’re still comparing options before you buy, here are Japan eSIMs compared on price.
Network
NTT docomo coverage in Japan
Your eSIM runs on NTT docomo, one of Japan’s major mobile networks. It’s a real Japanese line, with a Japanese IP address.
- The NTT docomo network5G where the network and your phone support it, 4G elsewhere, on the same network.
- A Japanese IP addressJapanese websites and apps see you as a local connection. Your data doesn’t take a detour through another country.
- Connected as soon as you landTurn off aeroplane mode when you arrive: your eSIM connects by itself. There’s no setting to switch on.
In practice, your data goes straight through the Japanese network. When you roam on a UK plan, it usually travels back to the UK before it reaches the internet. With your eSIM, it stays in Japan: the shortest route.
What it means day to day
- Maps and trains: your route and train times, whenever you need them.
- Translation: menus, signs and conversations, with your camera or microphone.
- Tickets and bookings: QR codes and confirmations always to hand.
Want to see where the network reaches? NTT docomo publishes its 5G and 4G coverage maps on its official website. The maps themselves are in Japanese.
Compatibility
Is your phone eSIM compatible?
You need a phone that supports eSIM and is unlocked. Search for your model: the answer appears straight away.
Type your phone’s name: the answer appears as you type.
Based on the lists from Apple, Samsung, Google, Xiaomi and Oppo, checked on 15 Oct 2026.
Every list, brand by brand: eSIM-compatible phones. Still not sure? Message us on WhatsApp before you buy and a real person will check with you. And if you buy in the app, it checks your phone before you pay.
Installation
Install it before you fly
Everything is done at home, before you leave. Installing takes 1 minute.
Buy your plan
On the website or in the app. Your QR code arrives straight after you pay.
Install your eSIM at home
On Wi-Fi, before you leave: from the app, or by scanning your QR code. Your UK SIM stays where it is.
Land, and you’re connected
Turn off aeroplane mode: your eSIM connects to the Japanese network by itself. Your plan starts with this first connection.
Step by step, screen by screen: set it up on iPhone or set it up on Android. The whole journey is explained step by step, from purchase to connection. Stuck during installation? Support answers on WhatsApp, 24/7.
Words worth knowing
- eSIM: a SIM built into your phone. Your plan downloads instead of going into a SIM tray.
- QR code: the code you get after you buy. You scan it to install your eSIM.
- Top-up: extra data you buy during your trip.
- Hotspot: your phone acts as a Wi-Fi access point for another device.
In the app
Top up and track your data in the app
With the Mobile Companion app, you can follow your data and top up your plan, even in the middle of your trip.
- Track your data: see how much you’ve used, and find your eSIM in your eSIM list with its status.
- Top up: choose a top-up and pay in the app.
- No app? You can also top up from your account on the website.
Manage it all in the app
Buy, install and top up your eSIM from your phone, with the same account as on the website.
A quick look in the morning before a long day of sightseeing, and you know where you stand. No nasty surprises halfway round Kyoto. Every feature, with real screenshots: top up in the app.
Reviews
Japan eSIM reviews from our travellers
Reviews our travellers have left on the App Store, quoted as written, in their original language.
Rated 5.0 out of 5Average rating on the App Store · 26 ratings
Rated 5 out of 5
Une expérience incroyable
« J’ai testé la eSIM pour la Corée du Sud, le Vietnam et quand je suis revenu en France en vacances. Et franchement c’était incroyable. Aucun problème, une qualité de fou, la vitesse d’internet était au top. Je recommande fortement ! »
MrLaugx
Rated 5 out of 5
Parfait !
« Je suis très content de cet esim, elle marche parfaitement et a un prix très raisonnable ! »
Les moustics volants
Rated 5 out of 5
Super application Esim
« Super application de esim , des prix défiant toute concurrence.Je vous recommande Companion mobile pour votre séjour au Japon !! »
enzoo_stt
Rated 5 out of 5
Franchement c'est le moins chère
« Bein ça fait grave le taff. Je vois quoi dire d'autre. »
Eagleroro
Rated 5 out of 5
Top !
« Application très intuitive, facile d’utilisation et extrêmement utile en cas de voyage au Japon pour me faciliter la vie en plus des prix très abordable »
_.yass.
From the UK
Travelling from the UK
Your UK plan may let you roam in Japan, but a Japanese data eSIM is usually simpler: you choose your data before you fly, and it runs on a local network.
A local eSIM or roaming on your UK plan?
- A Japanese line: your eSIM runs on NTT docomo, with a Japanese IP address, and connects by itself when you land. There’s no roaming setting to switch on.
- A plan you choose in advance: you pick your data before you go and pay once. If you need more, you top up from the app or your account.
- Your UK number stays put: your UK SIM stays in your phone, so you can still get calls and texts, such as your bank’s security codes, depending on your UK plan.
Roaming terms are different for every UK plan. Check your UK network’s own roaming terms before you go, especially for calls and texts you send or receive in Japan.
Paying in euros from a UK bank account
Our prices are in euros. When you pay with a UK card, your bank converts the amount into pounds and may charge a fee for it: your bank or card provider can tell you what applies.
Before you leave the UK
- Check that your phone supports eSIM and is unlocked.
- Check your UK network’s roaming terms for calls and texts.
- Buy your plan and install your eSIM at home, on Wi-Fi.
- Keep your UK SIM switched on, but turn off data roaming on it, so it doesn’t use data abroad. On iPhone, it’s in Settings > Mobile Service (Mobile Data on older versions), under your UK line.
FAQ
Japan eSIM FAQ
Do I need an eSIM for Japan?
Not strictly, but it gives you maps, trains and messaging from the moment you land, without hunting for Wi-Fi. And it’s already in your phone: there’s nothing to pick up or hand back.
Can I buy a Japan eSIM from the UK?
Yes. Buy it here, online, or in the Mobile Companion app before you fly. Your plan only starts when you first connect in Japan, so you can buy it days ahead.
How do I receive my eSIM?
Your QR code arrives straight after you pay. You then install your eSIM in 1 minute, from the app or by scanning that QR code.
How much does a Japan eSIM cost?
From €1.20 for the smallest plan. The 10 GB plan costs €8.60 and the 50 GB plan €28.90, which is €0.58/GB. Every plan is listed at the top of this page with its validity and price per GB, in euros. When you pay with a UK card, your bank converts the amount into pounds and may charge a fee.
Is there an unlimited data plan?
No: every plan comes with a set amount of data, shown with its price. The largest, 50 GB, costs €28.90, and if you run low, you can top up from the app or your account on the website.
Which network does the Japan eSIM use?
NTT docomo, in 5G where it’s available and 4G elsewhere. It’s a Japanese line, with a real Japanese IP address.
Does the Japan eSIM come with a phone number?
No, it’s a data-only eSIM, so there’s no Japanese number. Your UK number stays on your usual SIM for calls and texts, WhatsApp keeps your account, and you can call over WhatsApp or FaceTime using the eSIM’s data.
When should I install and switch on the eSIM?
Install it at home on Wi-Fi, before you leave. When you land in Japan, turn off aeroplane mode: it connects by itself.
When does my plan start?
When you first connect in Japan, not when you buy it. So you can buy it several days before you fly.
Do I need to switch anything on when I land?
No. Your eSIM is a Japanese line: it connects by itself, with no setting to switch on.
Can I use my eSIM as a hotspot?
Yes, hotspot and tethering are allowed. Just allow for more data if other devices connect to it.
Can I top up during my trip?
Yes, from the app or your account on the website, whenever you like.
I’m going for two weeks: which plan should I choose?
One whose validity covers your whole stay, with enough data for the way you use your phone: 5 to 10 GB for moderate use, so €4.80 to €8.60. The calculator on this page suggests the plan that’s enough, based on what you do in Japan.
We’re travelling as a group: what’s best?
Either one eSIM each, or one larger plan shared from a single phone, since hotspot use is allowed. Choose whatever is easiest for your group.
Does the eSIM work on iPhone?
Yes, on eSIM-compatible iPhones: every model since the iPhone XS and iPhone XR, except some sold in China mainland, Hong Kong or Macao. Your iPhone must also be unlocked. You can check your model in our list of eSIM-compatible phones.
And on Android?
Yes, on eSIM-compatible Android phones, such as Google Pixel phones since the Pixel 3a and most recent Samsung Galaxy models. The app checks your phone before you buy.
eSIM or pocket WiFi: which should I choose?
An eSIM is already in your phone: there’s no device to collect, keep charged or return. A pocket WiFi can make sense if your phone doesn’t support eSIM.
Physical SIM card or eSIM?
A physical SIM card usually takes the place of yours in the SIM tray. An eSIM installs alongside it, so your UK SIM stays where it is.
What do travellers say about your Japan eSIM?
You can read the reviews they’ve left on the App Store on this page, quoted as written, with the app’s average rating.
Who sells these eSIMs?
Mobile Companion, which sells data eSIMs for Japan on this website and in the app.
Got a question before you buy?
Message us on WhatsApp: a real person replies, 24/7, in English or French. You can also email contact@mobile-companion.com.
- When to switch it onThe right moment to install your eSIM and to connect.
- eSIM or pocket WiFi?Two ways to get online in Japan, side by side.
- Japan SIM card or eSIMWhat changes between a physical SIM card and an eSIM.
- Who Mobile Companion isThe company behind these eSIMs.
Something else on your mind? You can ask a question before you buy, message us on WhatsApp, or find more answers in the help centre.