Quick answer: Stack discounts only when the terms explicitly allow it, and calculate each benefit in the order applied at checkout.
What stacking means
Stacking combines two or more benefits, such as a sale price, coupon, bank discount and loyalty credit. Retailers often restrict combinations, so visible promotions should not be assumed to work together.
Use the checkout order
Start with the listed selling price. Apply an allowed coupon, then calculate any percentage benefit on the eligible remainder. Add fees and delivery. Subtract only cashback that is sufficiently documented, respecting its cap and delay.
Common conflicts
A sitewide code may exclude already discounted products. Bank discounts may require a minimum amount after coupons. Wallet cashback may exclude gift cards or bill payment categories. Loyalty points can reduce the amount on which another reward is calculated.
Do not buy extra to unlock a weak benefit
Increasing a basket to meet a minimum spend is worthwhile only when the added items were genuinely needed and the net cost is lower. Spending ₹500 more to unlock ₹100 is not a saving by itself.
Verify before authorization
The checkout summary is the authoritative transaction amount. If an expected instant discount is absent, stop and review the terms. Do not assume support will add it later unless the provider explicitly documents that process.