Greetings, @Hello265. You have a few easy options for adding bank details to your invoices. First, you can configure your payment instructions to include your bank details. This setting then automatically applies to all new invoices. Simply go to Gear icon > Account and settings > Sales > Invoice Payments — Payment instructions/options. I've included a screenshot below for your reference.

Alternatively, you can type the information directly into the Notes to customer section on the invoice page. This is a great choice if you want more control or need to customize details for specific clients. Just remember to select the Show full details in email checkbox under Online delivery in the Sales menu. This ensures your payment instructions or notes appear directly in the email text rather than just in the PDF attachment.

If you prefer to skip those settings, you can instead input your bank details in the Messages section (also under the Sales menu). This applies the bank details directly to the body of all your emailed invoices.
Don't hesitate to leave a comment below if you have any questions about managing your invoices or sales transactions.