The amount due should never be a mystery. Discount, tax, and shipping are easy to mix up if you hide them in a single lump sum. Show each adjustment, then a final total.
Discount
A discount reduces the subtotal. Use it for a launch offer, a retainer courtesy, or a pre-agreed percentage. Label it so the client knows why the number dropped. InvoiceBizz can apply a discount amount before tax, which keeps the math predictable.
Tax
Tax rules depend on where you and the client operate. Many businesses add a percentage on the taxable amount after discount. Put your tax label in plain language, such as VAT or sales tax, and include your tax ID if required. If you are not charging tax, do not add a zero tax row just to fill space.
Shipping
Shipping or delivery is usually added after the discounted goods total. If shipping is taxable in your region, follow that rule in your bookkeeping even if the generator shows a simple extra line. For digital work, you can leave shipping empty. InvoiceBizz hides unused shipping on the preview.
Check the live total
Change one field at a time and watch the preview. If the grand total does not match your quote, fix the quote or the invoice before you send it. Clients notice mismatches immediately.
Try discount, tax, and shipping in the free invoice maker and download the PDF when the numbers look right.