How to split the receipt tax amount
If you want to apply a tax rate but not all items on the receipt are taxable, a taxable line item and a non-taxable line item need to be created.
To save you from manually calculating these amounts, these can be automatically generated by navigating to the Receipts page and open the receipt detail for your selected receipt by clicking the link in the Merchant column.
In the top right hand corner of the receipt detail window, click the cog icon with the down arrow. click on the Split Tax button in the drop down list.
Enter the actual amount of tax you want to apply to the receipt, then select the tax rate (for the taxable amount to applied to) and a non-taxable rate (for the remainder of the receipt to be applied to). Click the green Confirm button when you're ready.
The receipt tax amount will be updated to reflect the tax amount you entered, and two line items will automatically be generated - one for the taxable amount, and another for the remainder of the receipt (the non-taxable amount). Click the green Save Changes button to apply these changes.