You can display your product prices without tax by following the simple steps below.
For this feature works properly, you have your taxes set up correctly in your Shopify store. Simple Invoice will use these tax settings and automatically display all the required tax details on your invoices. There isn’t any configuration needed on the Simple Invoice side.
Step 1: Open Simple Invoice from your Shopify store’s “Apps” section.
Step 2: Click on the “Templates” on the Simple Invoice dashboard.
Step 3: Click on the Options section, and click on the Show Product TAX Excluded Unit Price under the Line Items.
Step 4: Click on the Save button.