Landing in Japan and want to be online the moment you switch off airplane mode? JAPAN-ON-LINE eSIM is a travel eSIM for Japan: buy it online before you fly, scan a QR code, and your phone connects to Japan’s NTT Docomo network when you arrive. No SIM card to swap, no pocket Wi-Fi to pick up and return at the airport, and your home SIM stays in your phone.
For readers of the Japan Adventurer blog, we’re pleased to offer a special deal: 10% OFF any JAPAN-ON-LINE eSIM plan. Open the shop through our link and enter the coupon code JA001 at checkout — the discount is applied to your order. Get your eSIM here.
JAPAN-ON-LINE eSIM Coupon
| Item | Details |
|---|---|
| Coupon Code | JA001 |
| Discount | 10% OFF the plan price |
| Expiry Date | No expiry date set (the offer may end without notice) |
| Eligible Plans | All plans — 30GB (8 days), 50GB (16 days), 100GB (31 days) |
| Where to Order | Online only — japan-on-line-esim.com |
| Minimum Purchase | None |
| Terms of Use | Enter the code at checkout before you pay. Cannot be combined with other coupons or discounts. Discounts cannot be applied after payment. |
How to Use the Coupon
- Check that your phone is unlocked and supports eSIM (iPhone XS / XR and newer, Galaxy S20 and newer, Pixel 4 and newer, and many others — see the compatibility checker on the site).
- Open the shop through our link, choose a plan, enter the coupon code JA001 at checkout and pay by credit card.
- Your QR code and setup instructions arrive by email, usually within 5–15 minutes. Install the eSIM while you still have Wi-Fi at home or at the airport.
- When you land in Japan, turn the eSIM line on, enable Data Roaming and set the APN to
ppsim.jp. That’s it — you’re online.
Important
- Your plan days start the first time the eSIM connects to a network in Japan — not when you buy or install it. If never used, the plan starts automatically 45 days after purchase, so buy within about six weeks of your trip.
- This is a data-only eSIM: no Japanese phone number, so use LINE, WhatsApp or similar apps for calls and messages. Hotspot / tethering is allowed on all plans.
- After you use up your high-speed data, the speed drops to 200kbps until the plan ends. There are no daily limits and no extra charges.
- Phones bought in mainland China, Hong Kong or Macau usually do not support eSIM. Carrier-locked phones must be unlocked first.
- Prices are charged in Japanese yen (tax included); US dollar prices on the site are estimates. Plan prices and coupon conditions may change — please check the official site before ordering.
Why Choose JAPAN-ON-LINE eSIM?
1. Online from the moment you land. Buy and install before departure, and your phone connects as soon as you turn the line on at the airport — no counter to find, no device to return on the way home. Support is available in English by email if anything goes wrong.
2. Japan’s top network, nationwide. Every plan runs on NTT Docomo with 5G / 4G LTE where available, covering all 47 prefectures — cities, Shinkansen routes and most of the countryside Japan Adventurer loves to write about. (Deep mountains, some tunnels and remote islands can still be patchy, as with any carrier.)
3. Generous data, simple pricing. 30GB, 50GB or 100GB of high-speed data with no daily cap, so maps, photos, video calls and uploads all come out of one big pool. The checkout price is the whole price: no shipping, activation fee, deposit or contract.
4. Extra perks for eSIM customers. JAPAN-ON-LINE eSIM customers get partner offers in Japan, such as a discount at a cocktail bar in Shibuya, karaoke at Big Echo and a travel stamp book — see the Coupons page on their site for current offers.
Plans
Prices as listed on the official site in October 2026 (tax included). Your 10% coupon discount comes off these prices.
- 30GB Data — 8 days — ¥4,565 (about US$31)
- 50GB Data — 16 days — ¥5,346 (about US$36)
- 100GB Data — 31 days — ¥9,999 (about US$67)
Not sure which to pick? Choose the validity that covers your trip first, then the data size: 30GB for maps, messaging and social media; 50GB if you make video calls or stream; 100GB for heavy use or sharing with travel companions by hotspot.
Stay connected across Japan with JAPAN-ON-LINE eSIM. Set it up before you fly, land, switch on — and don’t forget the Japan Adventurer reader coupon for 10% off: open the shop through our link and enter JA001 at checkout.