KDDI cuts Rakuten roaming coverage in 18 major cities from October

KDDI is reducing roaming service to Rakuten Mobile from October 1, 2026, withdrawing coverage from 18 major Japanese cities including Yokohama, Kobe, and Sendai. Rakuten subscribers in affected areas may experience connectivity issues. The reduction follows previous service withdrawals from Tokyo, Nagoya, and Osaka.

Quick Facts

KDDI reduces roaming service to Rakuten Mobile
Coverage withdrawn from 18 designated cities
Updated coverage map published showing pre- and post-October areas
Remaining roaming contingent on Rakuten base station development
KDDI

KDDI announced on September 30 that it will reduce roaming service to Rakuten Mobile starting October 1, 2026, scaling back coverage across 18 designated cities including Yokohama, Kobe, and Sendai. The reduction follows KDDI's earlier withdrawal from Tokyo's 23 wards, Nagoya, and Osaka. KDDI published an updated coverage map on its website showing service areas before and after the transition, allowing users to compare September and October coverage.

Under the new arrangement, roaming will end in areas where Rakuten has already deployed its own base stations. In remaining areas outside Rakuten's network, KDDI stated it will provide infrastructure support for a limited period, contingent on Rakuten's continued base station development. The roaming service area will be progressively reduced over time.

In affected areas, Rakuten Mobile subscribers may experience weaker signal strength and slower data connections, as the carrier relies on KDDI's network in regions where it has not yet built sufficient infrastructure. The scaled-back roaming model reflects the broader shift toward Rakuten establishing independent nationwide coverage rather than depending on KDDI's existing network.

Topics

Technology Business

#coverage reduction #KDDI #Japan #telecommunications #roaming #network infrastructure #Rakuten Mobile

Entities

Why This Matters

KDDI's roaming withdrawal affects Rakuten Mobile subscribers in 18 major cities starting October 2026, potentially degrading service quality in areas where Rakuten has not yet deployed independent infrastructure. The reduction continues a staged rollback (Tokyo, Nagoya, Osaka already withdrawn) and signals a shift in Japan's competitive telecom landscape: Rakuten must accelerate base station buildout to maintain nationwide coverage, while KDDI limits infrastructure support to areas with active Rakuten investment. Users in affected cities may experience weaker signals and slower data speeds.

Timeline & Sources

Sep 30, 2026

Wire

KDDI announces roaming reduction and publishes updated coverage map showing pre- and post-October service areas

Oct 1, 2026

Wire

KDDI roaming service reduction takes effect; coverage withdrawn from 18 designated cities including Yokohama, Kobe, Sendai