Why is Quickbooks charging GST on top of PST when I add a billable expense to an invoice?

Hello, 

A billable expense is an expense you incur on your customer’s behalf when you perform a work for them. You can easily record and track billable expenses so your customer can reimburse them when they receive their invoice. I'd be happy to explain why QuickBooks Online is recording GST on top of PST when you add your billable expense to QuickBooks Online. 

Adding a billable expense that's already been assigned a tax code means that the tax code will automatically apply these taxes when it's added to your invoice. QuickBooks is assuming that you're passing the entire cost of the expense (including the taxes) to the customer you're creating the invoice for. If you'd like to change the tax code and add a different one, you're able to do that by manually adjusting the tax code from the drop-down menu on the invoice. The total for the billable expense will stay the same. 

For example, if you have an expense for $100 and it has a combined tax of GST/PST at 12%, the total will be $107.00. When you add this expense to the invoice, the expense total of $107.00 will remain. You can adjust the tax code to HST at another 12%, for example, which will add a markup to your expense, now making the invoice total $119.84. 

If you add subsequent line items to your invoice, you're able to select different tax codes to each item, as QuickBooks Online calculates taxes by line item, not total. 

Here's more information about billable expenses: Enter billable expenses.

If you have any questions, or you'd like me to clarify anything, just let me know. 

Have a great day!