Japan eSIM
KDDI (au) and SoftBank on one eSIM, both with 5G. Scan it at home, land at Narita, Haneda or Kansai, and you're on the train with Google Maps before the doors close.
- Network
- 4G and 5G, local operators
- When your data runs out
- Slows to 128 kbps, you stay online
- Starts
- When you first connect at your destination
- Activate within
- 90 days of buying
- Hotspot
- Not confirmed for this plan yet
- Phone number
- None, data only (WhatsApp keeps working)
- Top-up
- Not yet: for more data, order a new eSIM next to this one
- Delivery
- QR code by email, usually within minutes
How much data for Japan?
Light is maps, messages and ride apps (about 0.25 GB a day). Normal adds socials and stories (about 0.6 GB a day). Heavy is streaming, hotspot and work: that's unlimited.
| Trip | Light | Normal | Heavy |
|---|---|---|---|
| 7 days | €6.993 GB, 30 days | €8.995 GB, 30 days | €18.997 days unlimited |
| 14 days | €8.995 GB, 30 days | €11.9910 GB, 30 days | €32.4915 days unlimited |
| 30 days | €11.9910 GB, 30 days | €18.4920 GB, 30 days | €53.9930 days unlimited |
The cheapest Japan plan that covers it. Your phone counts a little differently from the network, so keep some margin. More in our guide: how much data do I need?
Two networks, both with 5G
The Japan eSIM runs on KDDI, which you’ll see on your phone as au, and SoftBank. Both have 5G in the cities. Your phone connects to the strongest and switches by itself.
The third big network, NTT docomo, isn’t on this plan, and we’d rather say so. In Opensignal’s April 2026 report, docomo won the Coverage awards. au, however, won the most awards overall, including Reliability and Consistent Quality. SoftBank won Download Speed. With two of the three big networks on one eSIM, you have a fallback if one is weak where you are.
Where you’ll use it
Japan is a country you navigate with your phone, more than most:
- Trains: Google Maps knows every line, platform and transfer. You’ll check it constantly.
- Translating: menus, signs and the ticket machine. Camera translation uses data.
- Restaurants and queues: many popular places take reservations or queue numbers online.
- Cities: Tokyo, Kyoto and Osaka are where you’ll use the most.
Two things to know before you buy
No top-ups on this plan. The network behind it doesn’t allow them. When the data runs out on the 3 GB plan or bigger, you stay online at 128 kbps, which is enough for messages and basic maps, but slow for anything else. So size it generously: a bigger plan up front is cheaper than a second eSIM.
Hotspot isn’t confirmed for this plan yet. If you need to share your connection with a laptop, look at the Japan + Korea eSIM, which works in Japan too.
How much data for Japan
Two weeks with normal use (maps, translating, messages and socials) is about 8 to 9 GB, so 10 GB is the safe pick. Because you can’t top up, add a margin if you film a lot. The table above has today’s prices.
Going on to Korea?
Seoul is a short flight from Tokyo and Osaka, and plenty of trips combine the two. One eSIM for both is often as cheap as two local ones. See Japan and Korea for today’s prices.
Sources: Opensignal, Japan, April 2026. Networks, top-up and hotspot details per plan come from our own catalogue and supplier information.
Networks
Same data, smaller bill
| Plan | Rebels | Airalo | Nomad | Saily |
|---|---|---|---|---|
| 10 GB30 days | €11.99 | €16.04 | €14.25 | €16.03 |
| 20 GB30 days | €18.49 | €22.27 | €20.49 | €22.26 |
Competitor list prices checked on 22 October 2026 on esimdb.com, converted from USD at 0.89, without new-customer discounts. n/a means that brand has no matching plan. We only list plans where we are at least €0.50 cheaper than every brand that has one. Prices may have changed since.
Our promise
- Not installed? Full refund, no questions asked.
- Won't connect? We fix it with you. If we can't, you get a new eSIM or your money back.
- No QR code within 24 hours? Your money back.
Before you buy
Which networks will I be on in Japan?
KDDI (au) and SoftBank. NTT docomo, the third big network, isn't on this plan. Your phone picks the strongest of the two.
Can I use my phone as a hotspot in Japan?
We haven't had this confirmed for the Japan plan yet. Need a hotspot for your laptop? Then the Japan + Korea eSIM is the safer choice; it lists hotspot without restrictions.
Can I top up the Japan eSIM?
No. The network behind this plan doesn't allow top-ups. If you're unsure, take a size bigger: it costs less than a second eSIM.
Do I need a Japanese phone number?
No. The eSIM is data only. LINE, WhatsApp and your banking app keep working on your own number.
When should I install it?
At home, on wifi, a day or two before you fly. The plan only starts counting when your phone first connects in Japan.
What happens when my data runs out?
On the 3 GB plan and up you stay online: speed drops to 128 kbps, enough for messages and maps. The 1 GB plan stops when the data is used up. Need more? Order another plan in two minutes; it comes with its own QR code.
How does Unlimited work?
You get 1 GB a day at full speed. After that it's 5 Mbps until your daily allowance resets: enough for maps, socials and video calls. Then the next full-speed GB starts.
Can I keep my own SIM for calls and texts?
Yes. Your home SIM stays in, our eSIM does the data. Turn data roaming off for your home line and you won't get a surprise bill.
What if it doesn't work?
If it won't connect because of a fault on our side or the network's, we fix it with you. If we can't, you get your money back or a new eSIM, your choice. Never installed it? Full refund. The full rules are in our terms.
Travelling further?
One eSIM for the whole trip: these also cover Japan.
Or a local eSIM for the next country in Asia.
South Korea
Hong Kong
Indonesia
Malaysia
Philippines
Taiwan
Thailand
VietnamPrices checked against our catalogue on 24 October 2026. Prices include VAT.