Adding Data Field to Invoice for Cash Discount

Hello there, @SodicoUS.

At this time, adding two (2) total amounts in one (1) invoice is unavailable in QuickBooks.

However, you can create a discount item to apply it to your invoice. It could be a percentage or a fixed amount. Let me guide you how.

1. Go to your Lists menu and then click on Item List.
2. Choose the Item drop-down arrow and select New.
3. Click the Type drop-down and select Discount.
4. Enter the item name (Discount) and the description.
5. In the Amount or % field, enter the discount amount or percentage:
6. Go to the Account drop-down arrow and then click the income account you want to use to track discounts you give to customers.
7. Select the Tax Code drop-down arrow and choose a tax code for this item.
8. Click OK once done.

Next, here's how to add them on an invoice: 

1. Go to the Customers.
2.  Select Create Invoices.
3. Choose a customer on the Customer: Job field.
4. Record the necessary items.
5. Enter the Discount on the following line.
6. Click the Save & Close.

For additional resources, check out these articles: 

• Add, edit, and delete items
• Create an invoice in QuickBooks Desktop.

Fill me in if you have further questions. I'm always around if you need any help.

You can calculate an early-payment (or other) discount and include it on the invoice with a 3rd party add-on such as FormCalc SST for QuickBooks or CCRQInvoice (Google to find them).

In fact, if you go to the following page of FormCalc SST's Web site, and scroll down to "Tutorials and Examples", you'll find two articles about "Calculating a customer discount on an invoice":  https://bit.ly/2VOYUMb

It should be easy to adapt those examples to other kinds of discount calculations and messages, as well.

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