Related Questions:
I don't want a discount line showing on my Invoice
How do I remove the 0% discount on my Invoice?
How do I remove the discount section from my invoice?
Answer:
The discount line on Invoices is always visible in the Invoice editor. If you choose not to add a discount amount, this line will be hidden on the Invoice preview and client version of the Invoice.
Invoice editor (0% discount showing):
Invoice Preview/Client version (discount not showing):