Let me welcome you first to the Community, tombascoffee.
As the customer statement template comes from the invoice template(there is not a separate template for statements)To add your bank details to customer statements you would need to add them on the footer section of the invoice template. To do this go to the cog in the top right>custom form styles>edit (on the default template) select content> the bottom third of the preview> enter the bank details in the box for the footer of the template and save. Go back to the plus symbol on the top left and statements and then preview the statement and you will see the bank details at the bottom of the statement.
I also want to make sure you’re updated about the latest enhancements rolled out, so I’m adding a link where to view them. The QuickBooks Blog covers a wide range of topics that will help your business prosper.
Stay in touch if you have any other concerns. Please know I’ll be right here to answer them for you. Have a good one.
