You will receive an email informing you of the amount due.
Log in to My Y!mobile, tap the menu button in the top right corner of the page, then tap "Billing Information," then tap "Billing Confirmation Notification Settings."
(See How to Log In for instructions on how to log in.)
You can set the notification recipient and notification content.
To complete the procedure, please prepare your SoftBank ID (Y!mobile mobile phone number or alphanumeric ID) and My Y!mobile login password.
If you are using this service for the first time, please prepare your Y!mobile mobile phone number and PIN (4 digits).