Scroll down on the My au home screen and tap on "Smartphone, mobile phone, etc." [スマートフォン・携帯電話など] under "Charges up to yesterday" [昨日までのご利用料金] section .
3
Select the phone number you want to check and tap on "Select" [選択].
The phone number selection screen may not be displayed.
4
"Charges up to yesterday (estimated)" [昨日までのご利用料金(目安)] will be displayed.
If your rate plan has a limit on free calls, the remaining free call balance will also be displayed under "call charges" [通話料].