Japan eSIM at a glance
Japan eSIM plans on RoamingFlex start at €2.88 for 500MB over a day and run up to €57.49 for unlimited data over 30 days. Coverage uses NTT Docomo, SoftBank, and KDDI au, all three of Japan's major networks. 5G is live in every major city. 4G LTE is everywhere else, including most of the Shinkansen route. Activation takes about 90 seconds: scan the QR code in your phone's eSIM settings and you'll be online before customs at Narita or Haneda. No app to download, and no need to find a carrier shop with an English-speaking clerk. Works on iPhone XS and newer, Pixel 4 and newer, and the Galaxy S20 series and newer.
Networks
NTT Docomo, SoftBank, KDDI au (4G / 5G)
Activation
Under 90 seconds via QR
Currency
JPY (¥)
Capital
Tokyo
Plug type
Type A / Type B (100V)
Best time
March to May for cherry blossom, October and November for autumn colours. Avoid Golden Week (late April through early May) if you want fewer crowds.
Japan eSIM plans
Most-picked plans for Japan. Prices adjusted for local network costs. All plans include hotspot and tethering.
How a Japan eSIM compares
Carrier roaming
~€14/day
≈ €196 for 2 weeks
Typical international roaming charge from major EU/UK/US carriers in Japan. Caps often activate after €60/month and throttle to dial-up speeds.
Local SIM at airport
€15 to €40
one-time plus setup hassle
Local SIMs at Narita or Haneda kiosks cost €25 to €40 for a week of data. Activation needs your passport and takes 20 to 30 minutes.
RoamingFlex eSIM
€9.19
3GB / 15 days
Same plan covers 2 weeks of travel in Japan. QR code in under 90 seconds. No app, no airport queue, no passport scan.
How much data you actually need in Japan
Tourists in Japan average 320MB/day. Tourists in Japan typically use 300 to 400 MB per day. Google Maps for transit, translation tools (Google Lens beats every other option for menus), and the GO or Uber ride apps account for most of it. Free WiFi exists in cafes, train stations, and the big convenience-store chains (7-Eleven, Lawson, FamilyMart), but it's usually slow and login-gated, so people stop bothering after the first day. Source: RoamingFlex 22-destination data usage dataset (CC BY 4.0).
Insider tip
Download offline Google Maps for the prefectures you'll cross on the Shinkansen. JR East and Tokaido bullet-train WiFi exists, but it gets unreliable in the mountain tunnel segments, and you don't want to be the person trying to load directions through a 3-bar connection while everyone else gets off the train.
How to activate your Japan eSIM
- 1
Buy a Japan plan
Pick a plan above based on your trip length. Pay by card or wallet. Checkout takes under a minute.
- 2
Receive your QR code
You'll see the QR code on screen the moment payment clears and get a copy by email within 2 minutes.
- 3
Open your phone's eSIM settings
iPhone: Settings, then Mobile Data, then Add eSIM, then Scan QR. Android: Settings, then Network, then Add Mobile Plan or SIM, then Scan QR.
- 4
Land in Japan and turn on data roaming
Turn on data roaming for the new eSIM line (this is local data, not international roaming. The toggle is just how the OS routes traffic). You'll be online within 60 seconds of arrival.
Japan eSIM frequently asked questions
Will my eSIM work the moment I land in Japan?
Yes, as long as you scan the QR code and finish eSIM installation before you board. The eSIM connects to NTT Docomo, SoftBank, or KDDI au depending on signal, usually within 60 seconds of your phone leaving airplane mode at the gate.
Does the Japan eSIM cover the Shinkansen and rural areas?
Yes. Coverage is nationwide on 4G LTE, including the Tohoku, Hokuriku, and Kyushu bullet-train routes. 5G is widespread in Tokyo, Osaka, Kyoto, Nagoya, Fukuoka, and Sapporo. Signal can drop briefly in some mountain tunnels between cities. That's a physical-coverage limit shared by every Japanese carrier, not a plan issue.
Can I use my eSIM for tethering in Japan?
Yes. All RoamingFlex Japan plans include tethering and personal hotspot at no extra charge. iPhone hotspot, Android Wi-Fi Direct, and Bluetooth tethering all work.
How much data do I need for a one-week trip to Japan?
3GB is enough for most travellers. Google Maps navigation, translation, photo uploads to iCloud or Google Photos, and the occasional Netflix episode on the train all fit in that. If you livestream or vlog, jump to the 10GB plan.
Will my eSIM work in Okinawa and Hokkaido?
Yes. Coverage is nationwide including the main islands and the populated areas of Okinawa Prefecture and Hokkaido. Some remote islands have weaker signal regardless of which carrier you're on.
Do I need a Japanese phone number?
No. The eSIM gives you data, not a Japanese number. For voice, use Wi-Fi calling, WhatsApp, FaceTime, or LINE. LINE is the dominant messaging app in Japan, so install it before you arrive if you plan to coordinate with locals or hotels.
Can I keep my home number active while using the Japan eSIM?
Yes. The eSIM runs alongside your physical SIM as a dual-SIM setup. Set the eSIM as your data line and your home SIM as your call and SMS line. Incoming calls to your home number still ring while you're using Japanese data.
What happens if I overstay my plan validity?
Data stops the moment validity expires. You can top up by buying a new plan in the RoamingFlex dashboard. Same eSIM profile, new validity window. No need to scan another QR code.
More Asia destinations
Ready to travel Japan with mobile data?
QR code in 90 seconds. No app. No carrier shop.
Last updated 23 May 2026. Operated by Vektor Utility Holdings Limited (UK company 17174994).