How do you add income to a project specifically an existing business opening balance posted under income codes?

We've got some details to share on how Project features work in QuickBooks Online (QBO), Rebecca.

The option to add an opening balance from an income code to a project is unavailable in QBO. We'll need to create a new transaction like an invoice or bill and assign it to the project to track income and expenses. This will create a balance for the customer or vendor.  Here's how to add new transactions:

1. Go to Projects.
2. Find and select the project you want to add a transaction to.
3. From the Add to project ▼ dropdown, choose the type of transaction you want to add.
4. Enter the details for the transaction like you normally would.
5. Press Save and close.

You can check out this article for more details: Create and manage projects in QuickBooks Online and Accountant. If you need to enter opening balances, then we can create a journal entry. 

Once done, run the Project Profitability report to see the transactions under a specific project and this includes journal entries. Here's how: 

1. Go to the Projects tab.
2. Locate and click on the project.
3. Pick the Project Reports portion.
4. Tap View on the Project profitability section.
5. Click a specific amount from the report.
6. From the  Profit and Loss Detail report, you can see the Journal Entry.

Moreover, you can check out this article for more details about using project reports: Track hourly labour costs and profitability by project in QuickBooks Online.

If you ever come across any more concerns or ideas regarding projects or any QuickBooks-related, you're always welcome to reach out. We'll be here to help you and address any questions you may have.