Hi amlong24,
There isn't a way to automatically add those customise variables on the subject and message on the standard email of an invoice. I'd recommend to submit a feedback to our Product Development team to have this added on the future releases of QuickBooks Online. To submit a feedback:
- Select the Gear icon at the top, then Feedback.
- Enter your comments or product suggestions. Then select Next to submit feedback.
Your valuable feedback goes to our Product Development team to help improve your experience in QuickBooks Online.
Feel free to check on this link to see the new features for QuickBooks.
Let us know if you need further assistance. Have a nice day.
