Hi urbanwestservice,
Thanks for reaching out to Community. Welcome! QuickBooks Online is a superb cloud based accounting software for all of your bookkeeping needs. Having overdue invoices isn't something you want to see when managing your books, and I can see how concerning this can be. I'll be happy to share more details so you have the information you need to apply interest to overdue invoices.
Although there's currently no option for having interest automatically applied, you can add a finance charge to the invoice by creating the item. Here's how:
1. Click on the Gear icon in the top right and choose Products and Services
2. Hit New
3. Select Non-inventory or Service and give it a Name
4. Choose the Income account and then hit Save and close when done
Follow these steps to add the item to an existing invoice:
1. From the left menu open Sales and then Customers
2. Select the customer and look for Overdue invoices
3. Using the dropdown ▼ in the Action column, hit View/Edit
4. Add the interest as a line item and enter the amount
5. When finished, hit Save and send or Save and close
That's it!
In addition, you may be interested in getting started with QuickBooks Online Payments. This will allow your customers the option to make payment directly from the invoice when it's been received, so you get paid on time.
Please don't hesitate to reach back out if you have any other questions. We'd be glad to help!
