Hi @natasjaj,

There are a few customisation options for a customer statement in QuickBooks Online (QBO).

At this time, the option to include banking details in a customer statement is unavailable. What you can do is change the way transactions are listed.

Here's how:

1. Go to the Gear icon.
2. Select Account and settings.
3. Move to the Sales tab.
4. Scroll down to the Statements section, then click it.
5. You can choose to either List each transaction as a single line, or List each transaction including all detail lines.
6. Another option is to enable Show ageing table at bottom of statement.
7. Hit Save when you're done.

Open this article for additional details: Create and send customer statements in QuickBooks Online. 

Don't hesitate to tag me in a comment below if you have any other questions with QBO features. I'll get back to you as soon as I can.