Can i delete a customer from 2020?

Hi there, mark-delport. 

In QuickBooks, you can make the customer inactive. By doing so, the customer's name won’t appear as a choice for selection when creating your transaction. 

Also, please take note that when you inactive customers in QBO, the transactions associated with them remain in your company data Reports. Additionally, deleting a parent customer will include its sub-customers.

Here's how to make customer inactive: 

1. Click the Sales, then choose Customers tab.
2. Select the customer name, then on the Customer Details tab, click Edit.
3. Press Make inactive at the button, then Yes to confirm the deletion. 

If you have other questions for us, please click the Reply button below. I'll be right here to provide additional assistance whenever you need it. Have a lovely day!