On January 27 at around 14:00, Rakuten Mobile experienced a major service disruption affecting voice calls and data connectivity in parts of the Kanto region. The outage prevented users from making calls, browsing the web, and accessing online services for over an hour, prompting the carrier to issue an official apology and provide emergency contact instructions.
Outage Overview and Affected Area
The incident began shortly after 13:50, with the problem expanding rapidly around 14:00. Users reported inability to place calls, extremely slow internet speeds, or complete loss of service, especially in Saitama and surrounding prefectures. The disruption also impacted university networks and municipal websites, indicating a broader infrastructure effect.
Timeline and User Reports
- 13:50 – First user complaints received.
- 14:00 – Outage spreads across multiple Kanto locations.
- 14:30 – Rakuten Mobile posts official notice and apologizes.
- 15:30 – Partial restoration of voice and data services.
During the outage, Rakuten Mobile advised customers to use landlines or another mobile device to call emergency services (119) if needed.
Background and Recent Issues
Just two days earlier, on January 25, the carrier faced a 1 hour 20 minute MNP (mobile number portability) failure, which disrupted number transfers between carriers. While that issue was resolved by the evening, it highlighted ongoing stability challenges for Rakuten Mobile’s self‑operated network, launched in 2019 with the Rakuten UN‑LIMIT plan.
Infrastructure Challenges
Rakuten Mobile’s rapid expansion of its own 5G infrastructure has required significant capital investment. However, the relative newness of the network compared to established rivals has raised concerns about system reliability and fault tolerance, especially during peak traffic periods.
Business Impact and Future Outlook
The Kanto region is Japan’s economic hub, where remote work, online meetings, and e‑commerce rely heavily on stable mobile connectivity. An outage lasting over an hour can cause:
- Delays in business communications.
- Potential loss of sales and transaction opportunities.
- Disruption of educational and governmental online services.
Analysts suggest that Rakuten Mobile must strengthen its incident‑response protocols and enhance traffic‑prediction algorithms for the growing 5G load to prevent similar events.
Recommended User Actions
After service restoration, users should:
- Restart their device.
- Reset network settings if connectivity issues persist.
- Monitor Rakuten Mobile’s outage page for real‑time updates.
- Use alternative communication methods (landline, other carriers) for emergency calls.
Conclusion
The January 27 outage underscores the maturity challenges of Rakuten Mobile’s self‑built network. While the disruption was brief, its occurrence in the critical Kanto market directly affects the carrier’s reliability perception. Ongoing investigations and concrete preventive measures will be essential for maintaining competitive strength in Japan’s mobile landscape.
