As Xero based practice, when we're setting up your Xero file we might ask you to provide us with a CSV file of your bank transactions.
This is because Xero uses "bank feeds" that pull your bank statement data directly from your bank , but bank feeds only pull data that is created after the bank feed is set up. If we ever need to get bank transactions from a date before we set up your bank feeds (which is very likely if you're new to Xero) and add them into your Xero file, then we'll need to import these historical transactions as a CSV file, which comes from your internet banking history that only you have access to.
Each bank has a slightly different method for getting your transaction data out of internet banking. The guide below should help you do this if you belong to the major NZ banks.