I'm excited to have you join us in the QuickBooks Online community! It's a great place to find answers to your product and how-to questions. I can help you with recording an expense that includes tax.
QuickBooks Online keeps things simple when it comes to the expense and sales tax features. First, I want to make sure you have sales tax configured in your account. Here's how it's done.
Select Taxes in the left menu.
Click Set up sales tax.
Choose a Province or territory from the drop-down to get started (Note: You can set up more provinces and territories later).