GuroWorks Japan Guide

eSIM Not Working in Japan? Fix It in 5 Minutes

Short answer: in most cases the line is installed but not chosen for data, or Data Roaming is off. Do the checks below in order and stop when the internet works. Connect to hotel or airport Wi-Fi first so you can open the instructions from your eSIM provider.

iPhone: 6 checks, in this order

  1. Turn the line on. Settings > Cellular > tap the travel eSIM > Turn On This Line. (Apple: if a line is off, turn it on, then check for service.)
  2. Choose it for data. Settings > Cellular > Cellular Data > select the travel eSIM.
  3. Turn on Data Roaming for that line. Settings > Cellular > tap the travel eSIM > Cellular Data Options > Data Roaming. Apple names this the first fix for No Service or SOS abroad.
  4. Set the date and time to automatic. Settings > General > Date & Time > Set Automatically.
  5. Airplane Mode on for about 30 seconds, then off. Let the phone pick a network by itself.
  6. Still stuck? Contact the eSIM provider. Apple says to ask your carrier to check that the plan is active and set up for your device.

With two lines on, the travel eSIM is used for data but your home line can still charge roaming fees. Keep Data Roaming off for the home line.

Google Pixel (Android)

  1. Check the SIM list. Settings > Network & internet > SIMs. Make sure the travel eSIM is on and Mobile data is on.
  2. Set it as the data SIM. Under "Your primary SIMs", choose the travel eSIM for Mobile data. Only one SIM can be the default for data.
  3. Roaming on. Open the travel eSIM in the same SIMs screen and turn on Roaming.
  4. Network and APN. The same screen has Network and Access point names. Use the values in your eSIM provider's instructions; we do not list provider settings because they differ.
  5. Last resort: Settings > System > Reset options > Reset Mobile Network Settings. Google's page says this resets all your network settings.

Other Android brands (Samsung, Xperia and others) use different menu names. Google notes that options vary by phone and Android version; look for SIMs or Connections > SIM manager.

Before you blame the eSIM

CheckWhy
Phone supports eSIMApple: iPhone XS, XS Max, XR or later.
Phone is not carrier-lockedApple: a locked iPhone cannot use another carrier's eSIM.
Wi-Fi when installingApple: Wi-Fi or a hotspot is needed to set up a travel eSIM (some eSIM-only models in some countries excepted).
Provider's plan is for JapanLook at the plan name and dates in the provider's app or email.

Left out on purpose: APN values and network names for specific eSIM providers, and Samsung or Xperia menu paths — we did not confirm these on official pages today.

Quick answers

Why does my phone say No Service or SOS in Japan?

Apple's checklist for travelers: make sure the travel eSIM line is turned on, then turn on Data Roaming for that line. If it still says No Service, switch Airplane Mode on for about 30 seconds and off again.

Why is my eSIM installed but no internet?

On iPhone with two lines, Cellular Data must be set to the travel line (Settings > Cellular > Cellular Data). If both lines are on, Apple says the travel eSIM carries the data but your home line can still charge roaming fees, so turn roaming off for the home line.

Do I need Wi-Fi to install a travel eSIM?

Apple says your iPhone must be connected to Wi-Fi or a hotspot to set up a travel eSIM; some eSIM-only models in some countries can activate without. Install it before you leave, or at the airport on Wi-Fi.

Can any iPhone use any travel eSIM?

No. Apple says the iPhone must support eSIM (iPhone XS, XS Max, XR or later) and must not be locked to a carrier. Check this before you buy.

More Japan trip guides: Japan trip checklist (all guides)

Official sources

Checked November 4, 2026 (JST). Menus can change with software updates; confirm on the official pages.