The Payment Certificate can be downloaded from My au (Web) for free.
Choose the au phone number/ID for which you want to save or print the Payment Certificate and click on "Select" [選択].
Click on "Payment Certificate" [支払証明書].
Select the Payment Certificate you want to save or print and click the "Download Payment Certificate for the Selected Period" [選択した期間の支払証明書のダウンロード] button.
The Payment Certificate for the selected billing month will be downloaded.
Print out if necessary.
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