How to build an invoice total
Order the calculation from subtotal to amount due.
1
Enter quantity and price
Multiply to get the gross line-item subtotal.
2
Apply the discount
Deduct the discount before calculating tax.
3
Add tax and shipping
Apply the tax rate to the discounted amount, then add shipping.
What does this tool do?
An invoice total starts with the line-item subtotal, subtracts any discount, applies sales tax to the discounted amount and adds shipping. Getting the order right matters because tax is usually calculated after discounts.
The Formula
Total = Quantity × Unit price × (1 − Discount %) × (1 + Tax %) + ShippingFrequently Asked Questions
Should tax be applied before or after a discount?
In most jurisdictions tax applies to the discounted price, because the discount reduces the taxable sale value. Check local rules for early-payment or trade discounts.
Is shipping taxable?
It depends on the jurisdiction and whether shipping is separately stated. Many places tax delivery charges when the goods themselves are taxable.