Note: To add Tax IDs and other custom information to an invoice you will need a billing address. You can set that in the Account page of the Billing section.
1
Go to Billing → Account
In your dashboard, navigate to the Billing section in the main menu.
2
Add custom invoice details
Scroll down to the Custom invoice details card and click Add custom invoice details.

3
Enter custom invoice details
In the Custom invoice details modal that opens, add your custom text and click Add custom invoice details.

