1. In the Home window on the Setup menu, choose Settings.
2. Click Customers and Sales and then Discount.
3. In the Early Payment Terms section, add or change the early-payment terms.
4. Click OK.
   

1. In the Home window, click on the Customer and Sales tab, and then the Customers icon.
2. Double-click on the customer's name to open their record.
3. On the Options tab, in the Early Payment Terms section, enter:
   • The discount rate
   • The number of days within which an invoice must be paid to receive the discount
   • The number of days within which the full amount of an invoice must be paid
4. On the File menu, click Save.
5. Close the customer record.

Method 3: Add or change terms on a customer invoice

1. Enter a sales invoice.
2. Depending on the payment method you have selected, there are different ways to enter the payment terms or early-payment discount:
   Pay Later

   In the Terms box, add or change the early-payment terms.

   Cash, Cheque, or Credit Card

   In the Early Payment Discount box, enter a percent rate.
   
   __
   
   With method 1 & 2 above, invoice creation should look like below:
   

   Note that the "Early Payment Terms" boxes still show when entering an invoice, but the preview output doesn't mention anything.
   
   Hope this helps!
   
   Warm Regards, 
   Erzsi