Openline pairs cleanly with a SoftBank (Japan) primary line. Your SoftBank (Japan) SIM (physical or eSIM) keeps handling your personal calls, SMS, and 2FA; Openline handles cellular data at travel prices.
How to set it up
- Install Openline as a second eSIM. Do not remove your SoftBank (Japan) line.
- Once both lines are visible, set Cellular Data to Openline for the country you're travelling in.
- Keep Default Voice Line on your SoftBank (Japan) line so calls to your regular number still reach you.
- Turn Data Roaming off on the SoftBank (Japan) line so it never accidentally picks up expensive roaming.
- Turn Data Roaming on on the Openline line — that's required for travel eSIMs by design (Openline isn't charged as roaming to you).
Notes for SoftBank (Japan) customers
- Wi-Fi calling on your SoftBank (Japan) line keeps working while Openline runs — a helpful failsafe when a hotel Wi-Fi is decent but a partner cell isn't.
- If you have SoftBank (Japan)'s built-in international roaming plan, disable it before your trip or you'll double-pay: Openline will handle data, and your SoftBank (Japan) plan will still bill you for it if left on.
- SoftBank (Japan) may occasionally push a "Welcome abroad" SMS. Ignore it — it's informational, not a bill unless you actually use their roaming.
Still stuck?
Reach Openline support 24/7 through any of these channels:
- Live chat — inside the Openline app or at openline.com
- Email — ask@openline.com
- WhatsApp — wa.me/15554842461
- Messenger — m.me/askopenline
- Contact form — openline.com/contact
- Social DMs — @askopenline on X, Instagram, Facebook, YouTube, TikTok
When you write in, include your purchase code (the OL-… code we emailed you) and, if the eSIM is already installed, its ICCID (Settings → Cellular → tap the Openline line). That's enough for us to find your plan and diagnose without back-and-forth.