Stacking rules with Shopify discounts

Your free gifts, discount rewards and free shipping all run through one Oxify discount. In Shopify's terms, a free gift is a product discount, a Discount reward is an order discount, and Free Shipping is a shipping discount.

Free Gift + Free Shipping

Stack natively. Both come from the same Oxify discount, so they can apply on the same order with no special configuration.

Free Gift + customer discount code

Both discounts have to allow the combination:

• Oxify side. Open Cart Editor → Settings → Discount Settings. Combine with other Order discounts, Combine with other Product discounts and Combine with other Shipping discounts are all on by default. Free gifts follow the Product setting. Click Save after changing them — Oxify re-applies these settings to its discount every time you save, so change them here rather than in Shopify admin.
• Code side. Open Discounts → (your code) → Combinations in Shopify admin and explicitly allow it to combine with product discounts and shipping discounts as needed.

These checkboxes apply to the unified discount; stores still on the older separate discounts migrate first (see Migrate to the unified discount function).

Multiple reward tiers

There is no "cumulative tiers" setting. What happens when a cart qualifies for several tiers depends on the reward type:

• Free Gift — Every tier the cart qualifies for adds its own gift.
• Discount — Only the highest tier the cart qualifies for applies. A 10% tier and a 15% tier don't add up to 25%.
• Free Shipping — Always 100% off shipping, so qualifying for several free-shipping tiers gives the same result.

Common gotcha

If a customer reports their code "won't apply", the cause is almost always a combination rule — check the code's Combinations in Shopify admin first, then the Oxify checkboxes above, before debugging the app.