If your Account number has been updated or changed by your Supplier, you can mass rename the Account number via an Account import. The Change account to column on the import template will allow you to rename the current Account number with a new one. It will also allow you to add the old Account number as an alias to the new number.
Top menu >> Accounts >> Under the ...More Menu >> Import
Download the blank Import Accounts template file.
Enter the details of the account that you would like to rename. In column I (Change account to), enter the new Account number.
Note: If you are using an existing Account import template, adding "Change account to" as column header in column I will give you this functionality.
For the Existing data, select Overwrite. For the Account number changes, you can choose to create the old account number as an alias or to not create the alias and just rename the Account. Then click Import.
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