How do I include an expense on a customer invoice on which we charge a markup without having the amount of the expense being included in our total sales value?

Hi @pierre@provacref,

When you use the Markup rate feature in QuickBooks Online (QBO), it hits the Markup account in your Chart of Accounts.

This specific account is an Income type, which means it's included in your total sales. If you want to include a markup on your billable expenses but don't want to include it in your sales amount, I suggest you contact your bookkeeper or accountant. They can advise you on how you can go about setting up your QBO for this process.

I suggest you open this article for more details about account detail types: Learn about account detail types on the Chart of Accounts. It includes a brief description of an account detail type, as well as pointers to help you check which works best for what you need. 

Tag me in a comment below if you have other queries about the Markup rate in QBO. I'll be around to help you out.