I'm trying to set up my first invoice but can't seem to add my companies bank details anywhere?

Thanks for dropping by the Online Community, luke10.

Let me welcome you first to the QuickBooks family. I'm here to clarify why you're unable to add the companies details.

In QBO, you can enter, add, and track transactions using your account. However, showing the bank details on the invoice is currently unavailable.

You may want to consider using the Go Cardless application to see the customers' bank information. This is one of the apps that are compatible with QuickBooks.

I'm adding a link with detailed information on how to set up and use Go Cardless when accepting customer payments.

This should help you move forward. Let me know if you get the chance to check the application. I want to make sure this is taken care of.