41.07 Mobile, Internet & Communications#

Getting online in Japan means juggling carrier paperwork, municipal alerts, and a mix of English and Japanese resources. This guide keeps the critical links and definitions in one place.

Major mobile carriers#

Carrier	Where to start	Notes
NTT docomo	New contract checklist	English summary of required documents, same-day SIM activation windows, and My Number usage.
au / UQ mobile	International support page	Multilingual hotline, SIM unlocking policy, and plan comparison in English and Japanese.
SoftBank / Y!mobile	New contract guide	Explains ID options (residence card vs. passport) and payment methods.
Rakuten Mobile	Self-service sign-up (Japanese)	Airport kiosks allow passport-based registration; the official guide shows screenshots of the eSIM workflow.

Bring your residence card, passport, and a domestic payment method (credit card or bank account) when visiting shops. Double-check your bank account handles one-time passwords before setting up auto-debits—domestic-payments-and-transfers covers the paperwork.

Budget-friendly providers (MVNOs)#

• “格安SIM” comparisons on ケータイ Watch (Japanese) track promotions and speed tests.
• IIJmio and povo2.0 accept credit cards, allow eSIM activation, and publish English FAQs.
• Use the MIC’s Telecom Service User Support Center if you encounter unfair sales practices or need mediation.

Understanding MNP (Mobile Number Portability)#

• MNP lets you keep your phone number when changing carriers. The Ministry of Internal Affairs and Communications explains the system in its English overview.
• Reservation codes stay valid for 15 days. Request them via your current carrier’s app or hotline before you apply elsewhere.
• Typical workflow:
  1. Gather your customer ID, residence card, and payment details.
  2. Request the MNP reservation:
     • docomo My docomo form (ログイン → 解約・お手続き → MNP予約番号発行)
     • au / UQ mobile support page
     • SoftBank / Y!mobile MNP guide
     • Rakuten Mobile番号移行案内 (Japanese)
  3. Activate the new SIM or eSIM within the validity window.
  4. Confirm the old contract terminated and check the final invoice.

Contract checkpoints#

• Cooling-off (初期契約解除制度): Door-to-door or phone sales can be cancelled within eight days using the MIC template linked on the Telecom User Support site.
• Renewal windows (更新月): Most fixed-term contracts allow penalty-free cancellation during the renewal month and the following month. Set reminders in your calendar—penalties often exceed ¥10,000.
• SIM unlock: Devices sold after 2015 must offer an unlock path within 100 days. Each carrier provides English instructions: docomo, au/UQ, SoftBank/Y!mobile, and Rakuten Mobile (Japanese).

Home internet & Wi-Fi#

• NTT East and NTT West publish availability maps and installation timelines for FLET’S fibre lines.
• The MIC lists certified fibre resellers on its 光コラボレーション事業者一覧 (Japanese) page—use it when comparing bundled mobile + internet offers.
• Short stays: 54.06 Public Wi-Fi Networks covers municipal hotspots, Japan Wi-Fi auto-connect, and pocket Wi-Fi rental tips.
• Installation visits require someone 20+ at home. Technicians will ask for your residence card; clear furniture around the optical outlet before the appointment.

NHK reception contracts#

• nhk受信料 explains who must pay reception fees and how to register bank or credit-card payments.
• Register via the NHK Plus app (Japanese) if you stream on phones or tablets only; it still requires identity verification.

Emergency alerts & disaster apps#

• j-alert summarises how the national warning system pushes missile, tsunami, and severe weather alerts.
• Carrier-specific alert pages: docomo, au, SoftBank, Rakuten Mobile (Japanese).
• The Tokyo Metropolitan Government disaster app offers multilingual notifications, maps, and shelter info.
• Keep 41.10 Disaster Preparedness and Go-Bag nearby for packing lists and drill routines that match these alert channels.

Digital communication tools#

• Many municipalities use LINE for push notifications. Search for the official account (東京都防災, 横浜市, etc.) after registering your address.
• Japan Post’s e-notification service emails delivery reminders. 54.04 Japan Post e-Notification documents portal setup, tracking, and redelivery options.
• Use MyPortal message notifications (see my-number-card—myportal) for tax refunds and childcare updates once your My Number card is active.

When moving#

• Review contract transfer or cancellation windows one month before your move. Providers often require fresh installation fees at the new address.
• Update shipping addresses for SIM cards, routers, and NHK correspondence in the same session you submit your Japan Post change-of-address request.