1. On the top menu bar of Retailer, click on Setup -> System.
  2. Click on the Accounting tab.
  3. In Banking Details, type in your bank account details.
  4. Click Save and Close.
The banking details should now show up on Customer statements / invoices / receipts. There may be other options that need to be ticked for each of them.
See Store Names for setting up alternative business details (including Bank, BSB and Account No.) for certain customers.

For Multi-Store, each location can have different bank details.
  1. From the Main Screen of Retailer, click on Setup -> Multi-Store
  2. Under Store Details, select a Store from the list
  3. Under each store are fields for Bank, BSB and Account No.
  4. Click Save and Close.