Hello, @marianne-britten.
Thank you for posting in the Community. I'm here to help apply your 5% rebate to your customers.
You can apply a discount on your customer's invoice. If the discount field is not showing when creating the sales transaction, you'll have to turn this on to enable the feature.
Here's how:
- Click the Gear icon on your QuickBooks account.
- Under Your Company, click Account and Settings.
- Go to the Sales tab on the left panel.
- Click the Sales form content section to open it and check the tick box for Discount.
- Click Save, and then Done.
When creating the invoice, you have the option to choose whether to apply it as discount percent or value.
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However, in QuickBooks Online you can only apply the discount on the whole transaction. If you need to discount each product line, you may refer to this related post for the workaround: https://quickbooks.intuit.com/community/Other-Questions/discounting-for-each-product-line/m-p/321478.
Additionally, you can refer to this article for some helpful details about setting up a discount for early payment: How to give your customers a discount for early payment.
Keep me posted if you have other questions about the process. I'm here to help however I can.