Problem Zlash Price Intelligence fixes · 3 of 4
The coupon stacking problem
The five common stacking patterns
| Pattern | Behaviour |
|---|---|
| Coupon excludes bank offer | Most common pattern on major Indian marketplaces. Apply coupon → bank instant discount disabled. |
| Bank EMI excludes UPI offer | Choosing no-cost EMI on a card disables a separate UPI cashback that would have applied to a one-shot payment. |
| Coupon excludes coupon | Cart accepts only one promo code at a time; the second overwrites the first. |
| Wallet bonus excludes EMI | Some wallet topup-bonus offers do not apply to EMI conversions of the same card. |
| Stack-permitted | Reward points always accrue alongside any other discount; merchant-credit-balance redemption usually stacks with bank offers. |
Why the rules are not advertised
- Per-offer T&C buried in the offer page. Each offer carries its own "not applicable with" clause. There is no cart-level summary that aggregates them.
- Cart UI shows a single price. The cart re-renders the total when you apply a code; it does not show what you would have paid had you not applied it.
- Merchant interest. The merchant's promo budget is finite; ambiguity around stacking rules absorbs some of the demand that would otherwise have realised the maximum discount.
The mental cost
For the buyer to optimise on a single cart, they need to (1) try the cart with the coupon and note the total, (2) remove the coupon and try with the bank offer instead and note the total, (3) sometimes try a third combination with EMI, (4) pick the cheapest. Almost no one does this; the coupon is applied first because it is the most visible affordance, and the larger bank discount silently does not register.
How Zlash Price Intelligence fixes it
- Maintains a per-merchant stacking rulebook — which discount classes mutually exclude each other on which merchant.
- For every (cart × buyer wallet) pair, evaluates each legal combination and computes the effective price.
- Surfaces the cheapest combination at the top, with the alternatives one click away — so the foregone discount is never invisible.
- Updates the rulebook as merchants change exclusion rules during festive cycles (a frequent change).
See the stacking-aware matrix
For any product, Zlash Price Intelligence shows the cheapest legal combination of coupon + bank offer + EMI + wallet on every merchant carrying the SKU.
Open Price Intelligence →