EOQ when discount is offered changes when:

1. With a quantity discount, EOQ rules become a comparative exercise. 2. The buyer compares the total cost at EOQ versus the total cost at the discounted order quantity. 3. If the total cost at the discount level is lower, the larger order size becomes optimal. 4. Hence EOQ effectively shifts when total cost at the discount is lower. _Source: ICAI BoS Inter Paper 3, Ch 2 "Material Cost", §2.5.3 ¶2_