b-mobile

b-mobile provides Prepaid SIM Card for visitors from outside of Japan

b-mobile's prepaid data SIM cards are offered by Japan Communications Inc., one of the most popular MVNOs in Japan.
PAYG SIM, one of their services, can be used for both voice call and data transmission, and it is the only prepaid SIM card service with a voice call feature among all the ones sold to tourists to Japan.
Note that a PAYG SIM card is not available for customers having a residential address in Denmark, Finland, or Sweden when customers purchase the card at retail stores or online. However, this does not apply when the customers purchase the cards at hotels. Identity verification is required for using PAYG SIM.
You can purchase their prepaid SIM card via their web site and they deliver it to the place you specified in Japan such as hotel and airport.
They do not open the maximum download speed to the public.

Official Site

b-mobile Prepaid SIM Card Plans

Prepaid SIM Cards for Overseas Residents

Even those who do not have an address in Japan can purchase online.

Due to covid-19, the number of companies offering Prepaid SIMs for travelers and short-stay visitors to Japan has decreased. Due to the declining demand for prepaid SIM cards, the prices and services of prepaid SIM cards have been changing. The demand for Prepaid SIM cards has also been affected by the decline in demand, and the products have changed.

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