Japan eSIM: how to buy one, install it, and what it costs

• Dial *#06#: if an “EID” line shows, the phone supports eSIM. On an iPhone you can also find the EID in Settings → General → About.
• The phone also has to be unlocked, that is, not locked to a carrier.
• Most iPhones sold in mainland China do not support eSIM. Newer mainland models such as iPhone Air, 17e and the 18 Pro do, but they cannot install a foreign eSIM while in mainland China: install it after you arrive, with Location Services on. They also hold at most two eSIMs. Many Hong Kong and Macao models do not support eSIM either. A phone with no EID cannot install an eSIM.

Japan has 7 plans today, from $1.90, lasting up to 365 days. 30-day plans: 1GB $1.90, 3GB $3.90, 5GB $5.80, 10GB $6.90. Choose by days and data: for a short trip that is mostly maps and messages, a small plan is enough; if you stream video, go bigger.

Tap a plan to buy it; the price is the same as here, and the order page is final.

1. 1Open Japan on Green Tea Mobile and choose the data and days.
2. 2Pay with Alipay, WeChat Pay or points.
3. 3Minutes after paying, the install code (a QR code) appears on the order page and in My cards, and is emailed to you.

You get the install code as soon as you pay, so you can install it at home on Wi-Fi before you leave (an eSIM iPhone bought in mainland China is the exception: install it after you arrive). Most plans only start counting when you first connect in Japan; a few start at payment, and the plan page says which.

iPhone

1. 1From iOS 17.4, open My cards in Safari, tap the one-tap install and follow the prompts.
2. 2Or go to Settings → Mobile Data (Cellular) → Add eSIM, choose Use QR Code and scan the code in My cards; you can also enter it manually with the SM-DP+ address and activation code.

Android

1. 1Open Settings → Network & internet (or Mobile network) → SIMs.
2. 2Choose Add eSIM, Download a SIM, or scan a carrier QR code.
3. 3Scan the QR code, or enter the activation code manually. The path differs a little between brands.

Only one phone, so you cannot scan the code on its own screen? Save the QR code image to your photos, then pick it from your photos on the install screen.

• iPhone: open Settings → Mobile Data, tap this eSIM, turn on Data Roaming, and set mobile data to use it.
• Android: open Settings → Mobile network or SIMs, tap this eSIM, turn on Data roaming, and make it the SIM for data.
• Keep data roaming off on your usual SIM and it runs up no roaming data charges; with international roaming on, it can usually still receive text codes.
• How much data is left and when it ends are shown in My cards. Running low? Add a plan there, with no reinstall.

What data roaming isGetting home text codes abroad

• Japan has four networks: NTT docomo, au (KDDI), SoftBank and Rakuten Mobile. A travel eSIM runs on one or two of them; the supplier does not publish which for each plan. Weak signal? In your phone’s mobile network settings, turn off automatic network selection and try another.
• Stations, convenience stores and cafés in the big cities often have free Wi-Fi, but it usually needs signing up and comes and goes; for maps and rides you still want your own data.
• Google Maps works well in Japan for trains and the metro.
• Hokkaido and Okinawa are in Japan: the same Japan plan works there.

• Deleting the installed eSIM: once deleted, it usually cannot be installed again.
• Scanning one code on two phones: an eSIM installs once, and works only on the phone it was installed on.
• Installed, but no data on arrival: first check Data Roaming is on for this eSIM.
• Data roaming left on for your usual SIM: the phone may use it for data and run up roaming charges.
• Installing on a mainland-China iPhone Air or 17e before you leave: it will not install in mainland China. Wait until you arrive, and turn on Location Services.
• Buying before checking the phone: iPhones from mainland China mostly cannot use eSIM. If it happens, an eSIM not yet installed can be refunded on its order page, in full, to points.