Land in Japan already online. A HelloSIM eSIM gives you instant 4G/5G data on Japan's top networks — no SIM swaps, no roaming bills.
Stepping off the plane at Narita or Kansai and hunting for Wi-Fi is no way to start a trip. With a HelloSIM eSIM, your phone connects the moment you land — maps, translation apps, and train times ready before you reach the baggage carousel.
Why use an eSIM in Japan
Japan is incredibly rewarding to explore, but it rewards the connected traveler. An eSIM is a digital SIM you install before you fly, so there is nothing physical to buy at the airport and no overpriced roaming.
Activate in minutes, keep your home number active
No queues at convenience stores or rental counters
Pay a fair flat rate instead of daily roaming fees
HelloSIM connects you to Japan's leading carriers — NTT Docomo, au (KDDI), and SoftBank — for broad 4G LTE and fast 5G coverage. Cities like Tokyo, Osaka, and Kyoto enjoy excellent signal, and coverage reaches the Shinkansen bullet-train routes and most tourist regions too.
How to get connected
1. Buy your Japan eSIM on HelloSIM and check your email for the QR code.
2. Scan the QR code to install the eSIM (Settings then Mobile/Cellular).
3. Turn on data roaming for the eSIM line when you arrive — you are online.
How much data do you need
Light (1-3 GB): maps, messaging, occasional browsing for a short trip
Medium (5-10 GB): daily social media, photos, and navigation for a week
Heavy (15 GB+): streaming, hotspot, or remote work over two weeks or more
Japan has free Wi-Fi in many stations and cafes, so most travelers find a mid-size plan is plenty.
Good to know
Currency: Japanese yen (JPY)
Capital: Tokyo
Language: Japanese
Time zone: JST (UTC+9)
Don't miss: Fushimi Inari Shrine in Kyoto, Mount Fuji, and Tokyo's Shibuya Crossing
FAQ
Is my phone compatible? Most phones from the last few years support eSIM — iPhone XS and newer, Google Pixel 3 and newer, and recent Samsung Galaxy models. Your phone must also be carrier-unlocked.
When should I install it? Install at home over Wi-Fi before you fly. Activation only begins when you connect in Japan, so it won't burn data early.
Can I keep WhatsApp and my number? Yes. Your WhatsApp stays tied to your existing number, and the eSIM only adds data — so calls and apps work as normal.
Yes. eSIMs work well throughout Japan, which has some of the world's densest mobile coverage. A HelloSIM eSIM connects to major Japanese networks for data across cities, transit lines and most rural areas.
Is my phone compatible with a HelloSIM eSIM for Japan?
Most recent phones support eSIM, including iPhone XS and newer, Google Pixel 3 and newer, and recent Samsung Galaxy models. Your phone also needs to be carrier-unlocked to use a third-party eSIM in Japan.
How do I check if my phone is unlocked before traveling to Japan?
If your phone is fully paid off or bought outright it's usually unlocked. If you're still on a carrier installment plan, contact your provider to confirm it's unlocked before you rely on an eSIM abroad.
How do I buy a HelloSIM eSIM for Japan?
Select a Japan data plan on the HelloSIM website or app, pay online, and you'll get a QR code and setup instructions by email within minutes so you can install it before departure.
How do I install the Japan eSIM QR code on an iPhone?
Go to Settings > Cellular > Add eSIM > Use QR Code and scan the code from your HelloSIM email. Label it 'Japan travel' so you can easily switch to it when you arrive.
How do I install a HelloSIM eSIM on Android for Japan?
Open Settings > Network & internet > SIMs > Add eSIM (or Download a SIM instead) and scan the HelloSIM QR code. The exact wording varies on Samsung, Pixel and other brands.
Can I set up the Japan eSIM without scanning a QR code?
Yes. Use manual entry with the activation details in your HelloSIM email, which is useful when you're reading the email on the same phone you're installing the eSIM on.
Which networks does HelloSIM use in Japan?
HelloSIM connects to Japan's major operators such as NTT Docomo and SoftBank, chosen for the strongest local signal, which gives you the wide, reliable coverage Japan is known for.
Is there 5G coverage in Japan with an eSIM?
Yes, 5G is available across Tokyo, Osaka, Kyoto, Nagoya and other cities where the network and your plan support it. Elsewhere you'll get fast, dependable 4G/LTE that handles maps, translation apps and streaming easily.
How reliable is coverage in rural Japan?
Very reliable. Japanese networks cover cities, the shinkansen routes and most countryside and coastal areas well. Deep in the mountains or remote islands you may see weaker signal, as with any carrier.
How much data do I need for a week in Japan?
For a week of maps, translation, transit apps, messaging and browsing, many travelers use around 3 to 6 GB. If you stream a lot of video or use a hotspot, consider 8 to 10 GB or an unlimited-style plan.
How much data should I get for two weeks in Japan?
A two-week trip with everyday use typically fits in roughly 8 to 15 GB. Frequent video streaming, video calls or tethering can push this higher, so a larger or unlimited plan is a safer choice.
What Japan data plans does HelloSIM offer?
HelloSIM offers several Japan plans in different data sizes and validity lengths, from short stays to multi-week trips, so you can pick one that matches your itinerary.
How much does an eSIM for Japan cost?
The price depends on the data amount and number of days, with small short-trip plans costing only a few euros and larger plans costing more. See the HelloSIM Japan page for current pricing, as it can change.
How long is a HelloSIM Japan plan valid?
Each plan has a set validity, commonly from a few days up to 30 days, starting when the eSIM activates in Japan. Choose a validity that covers your whole trip so you don't lose days.
When does my Japan eSIM start counting down?
The validity period usually begins when the eSIM first connects to a network in Japan, not at purchase, so you can safely buy and install it before you travel.
Should I activate my eSIM before or after arriving in Japan?
Install it before you fly, but generally only enable the line and turn on data roaming after you land in Japan so validity starts on arrival. Follow the timing guidance in your HelloSIM email.
Will I have internet as soon as I land in Japan?
Usually yes. At airports like Tokyo Narita, Haneda or Osaka Kansai, switch on your HelloSIM line and enable data roaming after landing and you should connect within a minute or two.
Do I need to change APN settings for my Japan eSIM?
Usually the APN configures automatically. If you have no data after activating, HelloSIM's instructions include the correct APN to enter manually in your eSIM's cellular data settings.
Do I have to turn on data roaming in Japan?
Yes. The eSIM connects as a visitor on Japanese networks, so data roaming must be enabled for the HelloSIM line. It won't trigger extra fees because your data is already prepaid.
Can I keep my home number while using a HelloSIM eSIM in Japan?
Yes. Keep your regular SIM or eSIM active for calls and texts on your home number, and set the HelloSIM eSIM as your data line. Turn off roaming on your home line to avoid its charges.
How do I set up dual SIM so I don't pay home roaming in Japan?
Keep both lines on, assign the HelloSIM eSIM for cellular data, and disable data roaming on your primary line. You'll still get calls and texts on your home number without using its data.
Can I use my HelloSIM eSIM as a hotspot in Japan?
Yes, HelloSIM Japan plans support tethering, so you can share data with a laptop, tablet or a travel companion's phone. Keep in mind hotspot use, especially video, consumes data quickly.
Can I make calls and send SMS with a Japan eSIM?
HelloSIM plans are data-only, so they don't include a Japanese phone number for standard calls or SMS. You can still call and message over data using apps like LINE, WhatsApp or FaceTime.
Why is LINE useful with my Japan eSIM?
LINE is Japan's most popular messaging app, used for chats, calls and even bookings, and it works over your HelloSIM data. Installing it before your trip makes staying in touch and using local services easier.
What are the emergency numbers in Japan?
Dial 110 for police and 119 for fire or ambulance. These numbers work on any phone with network coverage, even without an active data plan.
Can I use my HelloSIM Japan eSIM in other countries?
It depends on the plan. HelloSIM offers Japan-only plans and broader Asia regional plans; if you'll also visit South Korea or other Asian countries, choose a regional plan that lists them.
What happens if I run out of data in Japan?
You can buy a top-up or a new HelloSIM plan from the app or website and keep using the same eSIM, so there's no need to reinstall anything or hunt for a store.
How do I top up my Japan eSIM?
Open the HelloSIM app or website, choose a top-up or a fresh data plan for your existing eSIM, and pay online. The new allowance is typically added to your line within minutes.
How do I check remaining data on my Japan eSIM?
Track your remaining balance in your HelloSIM account, and your phone's cellular data usage screen also shows how much the HelloSIM line has used so you know when to top up.
My Japan eSIM says no service. What should I do?
Check that the plan is activated, data roaming is on for the HelloSIM line, and Airplane Mode is off. Then toggle Airplane Mode, restart the phone, or manually select a Japanese network.
My eSIM won't register on a network in Japan. How do I fix it?
In cellular settings pick the HelloSIM line, turn off automatic selection and manually choose an operator like NTT Docomo or SoftBank. Restart the phone afterward and confirm data roaming is enabled.
Why is my Japan eSIM slow, and how can I improve it?
Speeds may dip in very crowded areas or if you're on 4G rather than 5G. Try moving, restarting the phone, or manually selecting a different partner network. Japan's networks are generally very fast for streaming and video calls.
Does the eSIM work on the shinkansen bullet train?
Yes, coverage is good along shinkansen routes such as Tokyo to Kyoto to Osaka, though you may notice brief signal drops in long tunnels, which is normal for any mobile network.
Does the eSIM work on the Tokyo and Osaka subways?
Yes. Major metro systems in Tokyo, Osaka and other cities have strong underground coverage, so you can keep using maps, transit apps and messaging while riding the subway.
Can I install the Japan eSIM before my trip and activate it later?
Yes, and it's recommended. Install it at home on Wi-Fi so it's ready, then enable the line and data roaming when you arrive so the validity period starts in Japan.
Can I use one HelloSIM eSIM on two devices?
No. Each eSIM installs on a single device and can't be scanned onto two phones at once. For two devices, buy a plan for each or share your connection using the hotspot feature.
Do I still need pocket Wi-Fi in Japan if I have an eSIM?
Usually not. A HelloSIM eSIM covers maps, translation, transit and messaging without carrying a separate pocket Wi-Fi device to charge and return, though hotel Wi-Fi is handy for large downloads.
Can I get a refund on my Japan eSIM?
Refund eligibility generally depends on whether the eSIM has been installed or activated. Review HelloSIM's refund policy at checkout and contact support before activating if you think you chose the wrong plan.
Any tips for using a HelloSIM eSIM smoothly in Japan?
Install the eSIM before flying, download offline maps of Tokyo, Kyoto and Osaka, add a transit app and a translation app, install LINE for local messaging, and enable Wi-Fi calling to still receive home calls over data.
Can I use the Japan eSIM for navigation and translation apps?
Yes. The data plan works well for Google Maps, transit routing and live translation apps, which are especially useful in Japan. For peace of mind, download offline maps and translation packs before you go.
