Turned off the Discountable option in an account if you do not want an invoice line coded with the account to be eligible for prompt payment discounts.
[Refer to Page 37 of the MoneyWorks v7 User Guide for more information.]
Discountable works with the "Prompt Payment Discount" (In the Pricing & Term tab of the Name). Assuming the customer enjoy 10% discount, all items except freight charges, if he settles his outstanding within 30 days from the invoice date. You can uncheck the "Discountable" checkbox of the Freight Charges account since it is not eligible for a discount even the customer paid within the payment terms.
Let's say the detail of an invoice (Price is inclusive of 7% GST):
Item 1 at $3,210 Item 2 at $7,490 Freight Charge at $535 Total of the invoice: $11,235
When the customer pays within 30 days of the given terms, the discounted amount will be $10,165. That is:
3,210 + 7,490 = 10,700 - 10% = 9,630 + 535 = 10,165
The "Discountable" feature helps prevent giving discount accidentally on a non-eligible account.