When editing an invoice, you can insert a note for your customer directly under the payment terms and the due date. This note is displayed at the top of the invoice.
At the end of each invoice below the invoice line you can add an additional note in the 'Invoice terms' field. This text is displayed at the end of the invoice between the total amount and the footer .
The text in both fields can be saved as default, meaning it will be added automatically on each invoice.
Many people use this field, for example, to store a note on the sales tax law for small businesses. "Small business regulation according to §19 UStG".