Thanks for getting back with the Community, Slevy7.

If you're referring to a balance forward, you can turn on your Show on invoice option on the Content tab while editing your invoice's custom template.

Here's how:
 

1. Use the Gear icon, then go to Custom form styles.
2. Find your custom invoice template and click its Edit option.
3. Access the Content tab, then open your template's Table section.
4. Turn on Show on invoice. This will display the Total Amount Due & Balance Due on both PDFs and emails.
5. Select Done.

I've also included a couple detailed resources about working with invoice templates which may come in handy moving forward:
 

• Set up & send progress invoices
• Customize invoices, estimates, & sales receipts

Please don't hesitate to send a reply if there's any questions. Have a great Tuesday!