I’m working on a Shopify store where we’d like to allow customers to stack multiple discounts (e.g., a sitewide percentage discount plus a product-specific discount).
I’ve been looking into Shopify Functions for discounts, but I’m unclear on:
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Whether Shopify Functions can be used to enable discount stacking.
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How backend discounts (e.g., automatic discounts or those created via API) interact with discount functions.
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If there are best practices or limitations when combining multiple discount types.
Has anyone implemented discount stacking successfully using Functions or backend discounts? Any guidance or examples would be appreciated!
- You can’t “stack” product discounts on top of each other. Each line item can only have one product discount. However, discount stacking is on the roadmap for Q1 2026: Apps in checkout
- Backend discounts and Shopify Functions use the same combinations system. They can be used together on orders, but you still can’t stack product discounts on top of each other. Buy X Get Y discounts have some special limitations with combinations.
- I would recommend taking a look at the Shopify helpdesk to read all the limitations of its combination system: https://help.shopify.com/en/manual/discounts/discount-combinations
Best,
Tobe
EDIT: Sorry, I didn’t realize this question was for a specific AMA, rather than addressed to the general community.
Today each line can have a single product-specific discount. Merchants often use compare-at pricing to apply site wide sales, which can be further reduced by product discounts. The only limitation of this approach is that the strike-through pricing only appears on product/collection pages and does not show in cart & checkout.
As Tobe mentioned above, we are planning enhancements to the Discount Function API to support multiple product discounts on the same line early next year.
The Discount Function API is used by apps (from the app store and custom apps) that provide discount types which can be configured by merchants in their stores.