Discount: If you are offering a discount to your valued customer, include the number here. They will appreciate it and remember good things about doing business with you.
What should your invoice include? - A professional header - The first item on your freelance invoice should be your business name, or your full name, in professional (and easy to read) font. The font size should be a little bigger than the rest of the text on the invoice, and possibly even bolded for emphasis.