Should I use public Wi-Fi?

Public Wi-Fi in Japan is often patchy and requires cumbersome registrations. Do not rely on it for navigation or emergency communication.

Will my home carrier's roaming plan work?

It will work, but it is almost always 3-4 times more expensive than local eSIM options. Only use this as a last resort.

Getting Reliable Mobile Data in Japan

The most efficient way to get data is to purchase an eSIM via an app like Airalo or Ubigi before you land. If your phone is locked or doesn't support eSIMs, rent a portable Wi-Fi device online and pick it up at the airport post office upon arrival.

Check your phone compatibility. Ensure your phone is unlocked by your carrier. Check if your model supports eSIMs (most iPhones from XR onwards and Pixel 3 onwards do). If your phone is locked, you must either unlock it or rent a physical Wi-Fi puck.
Choose your provider. For eSIMs, use Ubigi or Airalo—they have the best coverage and easiest installation. For portable Wi-Fi, services like Ninja WiFi or Japan Wireless are the standard; book them at least 3 days before your flight.
Install and activate. If using an eSIM, install the QR code or app profile while you are still on home Wi-Fi. Turn on 'Data Roaming' for the eSIM line only after you land in Japan. For Wi-Fi devices, pick them up at the 'Wi-Fi Rental' or post office counters located in the arrivals hall of your specific airport.
Managing your connection. Set your primary SIM to 'Voice/SMS' only and your eSIM to 'Cellular Data.' This prevents your home carrier from triggering expensive roaming charges.

Should I use public Wi-Fi?: Public Wi-Fi in Japan is often patchy and requires cumbersome registrations. Do not rely on it for navigation or emergency communication.
Will my home carrier's roaming plan work?: It will work, but it is almost always 3-4 times more expensive than local eSIM options. Only use this as a last resort.