How can I keep track of delivered orders on QBO?

Thanks for actively responding, @waynerichardwhee. At the moment, you can only mark an invoice as paid when you received the invoice payment.  As a workaround, you can add notes as delivered or fulfilled in the Memo field. 

Since we're unable to track delivered orders in QuickBooks Online (QBO) at this time, I'd suggest you search for  third-party apps that work well with QBO. We have a variety of listings to choose from. Here's how: 

1. Login as Master Admin or Company Admin in your QuickBooks Online account.
2. Select the Apps tab from the left menu. 
3. Search for an order tracker app that can fit your business needs. 

Just in case, I'm adding our best articles that will help you more about your inventories: 

• Set up and track your inventory in QuickBooks Online. It helps you in managing your inventory, guides you on how to enter non-inventory items to add them to your sales form. 
• Reorder inventory or supplies from vendors. It'll help you learn how to stay on top of items in the order, and how to track what you received from a vendor. 

Let me know if you have additional questions. We're always delighted to assist you some more.