I have open invoice last year. How can I add those open invoice to this year?

Hello there, @Tata1. 

Thanks for sharing your concerns today. In QuickBooks Online Advanced version, you can import multiple invoices in one go.

To prepare your spreadsheet, you'll need to fill in the required columns:

• Invoice number
• Customer
• Invoice date
• Due date
• Item amount
• Item tax code
• If your invoices have multiple line items, make sure each line entry has an invoice number, customer, invoice date, etc. just like in the sample spreadsheet.

Also, take note of the following:

1. If you collect taxes, just add the tax rate in your invoices in the spreadsheet. When importing, you can map the tax codes you created into QuickBooks tax codes.
2. You can map each of your column headings to the invoice fields during the import. Take a look at what's required to import invoices. Or you download this sample spreadsheet.
3. If your spreadsheet has new products or services it can be edited after importing.

Then, follow the step-by-step guide for this process in this help article: Import multiple invoices at once.

You'll also want to create and manage statements to show customers summaries of their invoices, payments, credits, and balances.

Get back here if you need more help. We're always around to guide you.

Thank you for your reply @katherinejoyceO , However, My Opening Balance will be the closing period of December 2021 and my open invoices start in October 2021. Isn't it possible to input transactions beyond the date of Opening Balance? And I'm also using Quickbooks Online Essentials only. Thank you in advance

Thanks for the additional details, Tata1.

In QuickBooks Online, you can add invoices beyond the date of your opening balance. I'll show how to do it:

1. Click the + New button, then select Invoice.
2. From the Customer drop-down menu, select a customer. 
3. Enter the invoice date and terms.
4. From the Product/Service column, select a product or service. 
5. Enter the quantity, rate and amount as needed.
6. Select a tax option if applicable
7. When you’re done, click Save and close.

If you have several transactions that needs to be entered, you can import them by following the steps provided by my colleague, katherinejoyceO. I'm also adding this article to help manage and track the status of your sales transactions: View sales transactions.

If you have any other concerns or further questions, please don't hesitate to drop them in the comment section. I'm always here to help.