I don't think that's possible, at least cleanly. When we have a credit from a vendor and enter it, it is linked to the customer/job. As far as I understand it, there is not way to add job items to a credit, that can only be done on a customer invoice. There is not option to "add items" to a credit from unbilled job cost items. Furthermore, you missed the question that is the main issue: when a credit is applied from any format, QB's looks at it as if it's a payment from the customer and includes it on the Cash basis sales tax liability detail. The below screenshot is a clear example. That credit for taxable sales is due to a credit to a customer. The customer has not paid the invoice yet, therefore why is it included on the cash basis report? I've asked this so many times, on tech support, they have no idea, they've requested it to the engineers, not sure why it's still wrong after all this time.