You can download au payment certificates in PDF format for the past 18 months, including the current month, from My au (Web).
Please see below for detailed instructions.
Tap on "Save/Print Invoice/Receipt/Payment Certificate" [請求書/領収書/支払証明書の保存・印刷].
Tap on "Invoice" [請求書].
Tap on "Save/Print Payment Certificate" [支払証明書の保存・印刷].
Select the phone number you want to confirm and tap on "Select" [選択].
Enter your PIN and tap on "Next" [次へ].
Select the invoice you wish to save or print and tap on "Download Selected Payment Certificate" [選択した支払証明書のダウンロード].
Tap on [OK] to download the payment certificate in PDF format.
Please print and use as needed.
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