KDDI has updated its roaming map for Rakuten Mobile, making information on roaming areas from October onwards available.
Rakuten Mobile, which entered the market in spring 2020, relied on KDDI for roaming connections while it expanded its service area nationwide. That contract expired in September 2026. From October onwards, roaming services will continue to be provided in some areas, contingent on Rakuten Mobile's own base station construction.
First, the Kanto region. The first map shows coverage from October onwards, and the second shows coverage as of the end of September. While there's a significant reduction, one could also argue that quite a bit remains.
As a result, roaming areas have significantly decreased, particularly in urban centers. Nevertheless, the impression is that quite a bit remains. For sparsely populated areas (rural areas), roaming will continue to be provided over a wide range, so there seems to be no drastic change in these locations as of October.
The reduction is more pronounced in the Kansai region.
It's clear that there's almost no change in the sparsely populated areas of the Chugoku Mountains.
Therefore, urban areas are of particular concern. Especially indoors, it's thought that many locations relied on the superior signal penetration of au's platinum band roaming. It remains to be seen what changes will occur in Rakuten Mobile's connectivity from October onwards.
