How to Choose a SIM Card in Japan

Learn the main types of SIM cards available in Japan and how to choose the right option for your situation.

To use a smartphone in Japan, you need a SIM or eSIM plan. Understanding the types and contract styles can help you avoid unnecessary cost and frustration.

Main types of SIM plans

1. Tourist or short-term SIM

• Often sold at airports, convenience stores, and electronics retailers
• Little or no Japanese needed
• Usually data only, with no voice calling
• Often valid for 7 to 90 days

2. Low-cost monthly SIM (MVNO)

• Often requires address registration, a bank account, and sometimes a Japanese phone number
• Usually affordable
• Can include both data and voice service

3. Major carrier contract

• The big three are Docomo, au, and SoftBank
• The sign-up process is usually in Japanese
• Higher monthly cost, but generally stable service quality

Watch out for SIM locking

Your phone needs to be unlocked to use a Japanese SIM. If you bought your phone overseas through a carrier, check before coming to Japan.

A practical order for long-term residents

1. Right after arrival: use a tourist SIM or eSIM so you can get connected immediately

2. After you have address registration and a bank account: switch to a monthly low-cost SIM if it suits your needs

Useful words on Japanese plan pages

• 月額: monthly fee
• データ容量: data allowance
• 通話: voice calling support
• SMS: text message support
• 契約期間: contract period
• 縛りなし: no long-term cancellation restriction