If you only changed your surname, you can do the procedure through My au. For procedures including also changing your name, you will need to visit au Style/au shop.
In addition, you can request an application form from My au website and complete the procedures by mail. Click here for details on the procedure (in japanese only)
After completing the name changing procedure on your au contract, please contact the au PAY Prepaid Card (au WALLET Prepaid Card) desk.
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