If i create a credit note to a particular invoice, how should i mention against that it is a credit note invoice????

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In QuickBooks Online (QBO), you can go ahead and apply a credit note when recording payment for a customer’s invoice.

If you haven't created a credit note yet, here's how to do it:

1. In QBO, go to the + New option at the top left to create a Credit note.
2. In the Customer dropdown, select the customer's name.
3. Enter the credit note details, such as the date and the amount.
4. Hit Save and close once done.

After that, here's how to apply it to an invoice:

1. Go back to the + New option at the top left and tick Receive payment or Receive invoice payment.
2. In the Customer dropdown, select the customer.
3. In the Outstanding Transactions section, choose the open invoice you want to apply the credit note to.
4. In the Credits section, pick the credit notes you want to apply.
5. For the open invoice in the Payment column, enter how much of the credit you want to apply.
6. Leave the Payment method, Reference no, Deposit to, and Amount received fields blank.
7. Fill out the rest of the form, including the Payment date, and ensure the total is correct after applying the credit note.
8. Hit Save and close.

For more insights about managing credit notes in QBO, I suggest checking out this article: Create and apply credit notes or delayed credits in QuickBooks Online.

For tips and other resources, I recommend visiting our website for reference: Self-help articles.

Reach out to me in the comment section below if you have any additional questions. I'll be more than happy to answer them. Have a great day!