Solved
Can a customer view a deleted invoice after it has been emailed?
I accidentally sent an invoice prematurely, I immediately deleted it from the app. Can the customer see the email that was originally sent?
It's nice to see you here in the Community, @bluebagwell.
I'm happy to give you some insights about deleted invoices in QuickBooks Online (QBO).
Once you sent an invoice to your customer(s), they will be able to view it and the option to delete it on their end is unavailable. If you deleted the invoice from the app or in QBO, it will only remove the transaction on the program itself. However, you can inform your customer that the sent invoice is an incorrect one. Then you can now create a new one.
Here is an article I've included about the differences between voiding and deleting transactions in QuickBooks Online: Void or delete transactions in QuickBooks Online.
In addition, here's an article that will help you in the future in case you accidentally deleted an invoice or transaction in QuickBooks Online. This will provide you the information of the deleted transaction and recreate it manually: Use the audit log in QuickBooks Online.
Reach out to me in the comment section if you have any other questions about handling your invoices. I'm more than happy to help. Have a great day!