SIM cards and pocket Wi-Fi in Japan: how to stay online
Free Wi-Fi is not everywhere. JNTO lists two main ways to get data: a prepaid SIM card for an unlocked phone, or a rental pocket Wi-Fi router. Reserve a router before you go.
Option 1: a prepaid SIM card
A prepaid SIM works only if your phone is ready for it. JNTO says to check these things before you buy.
- The phone must be SIM-free (not locked to one carrier).
- The phone must carry the technical standards conformity mark for wireless equipment in Japan.
- Buy the right SIM size for your phone: nano, micro or standard.
After you put the SIM in, you finish the "use settings" to register and set up the network. Follow the provider's guide.
Option 2: a pocket Wi-Fi router
A pocket Wi-Fi router is a small rental device. You turn it on, choose its network on your phone and enter the password.
- Your device must support Wi-Fi.
- Reserve in advance. JNTO says a prior reservation is the only way to guarantee the rental at the time you want.
- It is a rental, so you must return it after your trip. Ask the provider where and when.
How to choose
- Several companies sell SIMs and rent routers. The JNTO mobile tips pages list providers and a finder for where to buy.
- Plans, prices, data limits and validity periods differ by provider, so read the provider's page before you pay.
- A router can be shared by a group. A SIM is simpler for one person with an unlocked phone.
The JNTO pages do not cover eSIM. If you want an eSIM, check your phone's support and the seller's terms.
Backup plan
Even with data, download offline maps before you go. Free Wi-Fi is a useful backup (see our free Wi-Fi tip), but it is not available everywhere.
FAQ
Can I use any phone with a Japanese prepaid SIM?
No. JNTO says the phone should be SIM-free and carry the Japanese technical standards mark. Check both before you buy.
Should I reserve a pocket Wi-Fi router?
Yes. Same-day rental can sometimes work, but reservation is the only way to be sure.
Where can I find provider lists?
Use the JNTO mobile tips pages for SIM and router, linked below.
Sources
Related tips
- Free Wi-Fi in Japan: how to find it and connectLook for the "Japan.Free Wi-Fi" symbol. Free Wi-Fi in Japan comes from several providers, and each one has its own way to connect, so set things up before you need them.
- Power plugs and voltage in Japan: what to bringJapan uses 100 volts everywhere. Most phone and laptop chargers (100-240V) work fine, but single-voltage devices from 220-240V countries need a transformer.
- Emergency numbers in Japan: 110, 119 and the visitor hotlineWho to call in Japan: 110 for the police, 119 for an ambulance or fire, and a 24-hour English hotline for visitors.
- Safety tips: the disaster alert app for visitors to JapanSafety tips is an app supervised by the Japan Tourism Agency. It sends push alerts for earthquakes, tsunami and severe weather, in 15 languages.
- Suica and IC cards: how visitors can pay for trains and shopsA Suica is a rechargeable IC card for trains, buses, vending machines and many shops. Visitors can get a Welcome Suica card or use Welcome Suica Mobile on a phone.
Last checked: 2026-11-02. Rules and prices can change, so please confirm with the official sources above.