One of my contractors pays for multiple invoices and deposits for other jobs on the same check. How do I make a credit memo for his sub-customer when there is no invoice.

Welcome to the Community, @userkellie.

In QuickBooks Online (QBO), you can still make a credit memo to the sub-customer even if there's no invoice yet. You can then apply it later on to the invoice once created.

Here's how:

1. In QBO, go to the + New option at the upper left to make a Credit Memo.
2. Choose the sub customer's name, then enter the other necessary information in the desired fields.
3. Hit Save and close to complete.

Once the invoice is created, here's how to apply the credit memo:

1. Go back to the + New option and select Receive payment.
2. Choose the sub customer's name, then enter the other necessary information in the desired fields.
3. Select Save and close.

You also have the option to automatically apply credit memos to invoices. To learn more about this, I suggest checking out this article: Create and apply credit memos or delayed credits in QuickBooks Online.

Feel free to leave a comment below. I'm always here if you have further questions. Have an amazing rest of the day!