I am trying to add an invoice to a project.

Hi there, kas34145.

I'm here to share details about adding invoices to a project and help you do it in QuickBooks Online (QBO).

You can add any invoice to a project so long as it wasn't created from a quote and doesn't have attached time or billable expenses. If the invoice is paid and you add it to the project, the payment for the invoice will be disconnected.

To avoid charging the customer twice, follow these steps before changing the name of the customer in the invoice with the project name:

1. In QBO, go to the Settings icon at the top right.
2. Select Chart of accounts.
3. Click Account history on the account the payment was deposited.
4. Tick the payment for the invoice, then Edit.
5. Select the checkbox next to the invoice the payment is for, then choose the project from the Customer dropdown.
6. Hit Save and close.

I can see how having the option to add a paid invoice to a project with disconnecting the payment would be helpful for you. We'd love to hear your input. I recommend leaving feedback to notify our engineers about the feature you need. This way, they can consider adding it in future updates.

Refer to this article for the detailed steps on how to submit feedback: How do I submit feedback?

I'm also adding these articles that tackles managing projects in QBO future reference:

• Track income, costs, and profitability by project.
• Add existing invoices to QuickBooks Online Projects.

Please let me know if you have follow-up questions about this or anything else. I'm more than willing to answer them. Take care.