Welcome to the thread, @MDM18.
In QuickBooks Online, having a discount from a vendor will not affect the Cost of Goods Sold (COGS) of the Inventory item. If you wish to get this affected, then you can create a journal entry that will affect the COGS and the vendor balance.
To create a journal entry, here's what you'll need to do:
- In the left menu, select the + New button.
- Pick Journal Entry.
- Fill out the necessary fields.
- Choose Save and close.
However, before we proceed with the steps, I highly suggest consulting your accountant or accounting professional for guidance on which account receives the debit and credit side of the transaction.
Additionally, I want you to get the most out of QuickBooks for your business. You can check some articles that are designed to help you get acclimated with the software. They can be accessed at the following link: QuickBooks Tutorials.
If there's anything else I can do for you, let me know by commenting below. I'd be happy to further assist you. Have a great day.
