Welcome to Mayumi

It is a cheap SIM that can be used for both telephone and data (including 1GB), and the basic monthly fee starts from 990 yen (excluding tax).

■ Recommended for such people
-If you want to reduce your smartphone fee a little this month, you want to control your monthly fee yourself. → You can control the amount of data (monthly charge) by yourself.
-If you want to make your smartphone cheap, but you don't want to change your phone number.
→ You can take over your current phone number. Of course we also offer new numbers.

■ About service contents
This product is a product that includes voice communication and data communication.
* It is not possible to use only voice calls or data communications.

At the time of application, you can select a SIM compatible with docomo network or a SIM compatible with SoftBank network.

docomo network compatible SIM
Up to 1GB: 990 yen (excluding tax)
From 1GB to 3GB: ¥ 1,290 (excluding tax)
From 3GB to 6GB: ¥ 1,790 (excluding tax)
From 6GB to 10GB: 2,590 yen (excluding tax)
From 10GB to 15GB: 3,590 yen (excluding tax)
※ After using up 15GB, it will be used at low speed.

Softbank network compatible SIM
Up to 1GB: 990 yen (excluding tax)
From 1 GB to 3 GB: 1,690 yen (excluding tax)
From 3GB to 6GB: 2,390 yen (excluding tax)
From 6GB to 10GB: 3,190 yen (excluding tax)
From 10GB to 15GB: 4,390 yen (excluding tax)
※ After using up 15GB, it will be used at low speed.


After the contract, you can set the upper limit of data usage to 6GB / 10GB / 15GB.
You can change the settings at any time on the customer-specific page "My b-mobile".
Exceeding the set limit will result in low speed usage.
* You cannot set the amount of data that is already used.


20 yen / 30 seconds
When you make a call using the "b-mobile phone" app, which can be used for free, you can use it for half the normal call rate of 10 yen / 30 seconds.
In addition, you can add a "5 minutes unlimited call option (500 yen per month)" and use the "b-mobile phone" application to talk for up to 5 minutes per call for free. After 5 minutes, you can use it for 10 yen / 30 seconds.
* The usage of the "b-mobile phone" application is the same as the iPhone. No need to contact later.
* You can apply for the "Unlimited Calling 5 Minutes Option" later on the customer page.


Monthly fee: 500 yen (excluding tax)
Unlimited domestic calls (both mobile and landline) up to 5 minutes.
It is free for many times. After 5 minutes, a call fee of 10 yen / 30 seconds will be charged.
* Only outgoing calls from the "b-mobile phone application" are eligible for free calls.
* Some destinations are not applicable.
* If you do not apply for 5 minutes and do not use the app, domestic call charges will be 20 yen / 30 seconds (excluding tax).

■ Start procedure
1. Purchase a package.
(Please check beforehand if your model and SIM are compatible.)
2. Apply on the WEB site. You will need your email address, credit card and identity verification documents.
* MNP subscribers also need an MNP reservation number.
3. When you receive the SIM card, insert it into your device, set up your APN and start using it.
* In the case of MNP transfer, after the SIM arrives, switching procedure is required on the WEB site.

* Please read the notes carefully before purchasing.