Discounts like trade discount, quantity discount etc. are part of the normal trade and commerce. Therefore, pre-supply discounts i.e. discounts recorded in the invoice have been allowed to be excluded while determining the taxable value.
Discounts provided after the supply can also be excluded while determining the taxable value, provided two conditions are met, namely:
(a) discount is established in terms of a pre supply agreement between the supplier & the recipient and such discount is linked to relevant invoices
(b) input tax credit attributable to the discounts is reversed by the recipient
This applies when the buyer and seller are not related parties and price is the sole consideration.
Thus, in case C and D are not related to you, you need not collect the GST on the discounted value i.e. 28% of Rs.100 discount given to C and 28% of Rs.50 discount given to D.
