Can interest accrued on customer invoices be automatically calculated in QBs?

Hello sgobho, 

Glad to have you join the Community. QuickBooks is a versatile program that helps you streamline your work using the powerful features offered in the program. Rest assured, I'll be happy to share more info so you're on the right track. 

The function you've described isn't available in the program. I can see the benefit of having this function for your business and I encourage you to send feedback about this to our engineers. You can send feedback by clicking on the Gear icon and looking for Feedback. New product ideas and improvements are based on the feedback we get from users like you.

Feel free to ask other questions. I'll be here to assist.