Shopify Discount Combination Checker
Enter your discounts and a sample cart to see which ones Shopify applies, why the others don't, and what the shopper pays.
Your cart and discounts
Cart total after discounts
$152.80
2 of 3 discounts applied. The shopper saves $46.20 on a $199.00 cart.
- Total saved
- $46.20
- Effective discount
- 23.2%
- Discounts applied
- 2 of 3
Breakdown
- Items subtotal
- $191.00
- Autumn sale
- −$38.20
- FREESHIP75
- −$8.00
- Shipping
- $8.00
- Total
- $152.80
Discount by discount
Autumn sale (automatic, product discount): applied, saves $38.20.
WELCOME10 (code, order discount): not applied, because WELCOME10 isn't set to combine with product discounts, and Autumn sale isn't set to combine with order discounts. Shopify applies the combination that saves the shopper the most ($46.20 here). On its own, this discount would save $19.10.
FREESHIP75 (code, shipping discount): applied, saves $8.00.
The rules Shopify uses
Every discount belongs to one of three classes: product (amount off products, buy X get Y), order (amount off the order) or shipping (free shipping). Each discount's Combinations setting says which classes it can join.
- Both sides must agree. Two discounts combine only if each one is set to combine with the other's class.
- Order of calculation. Product discounts come off first, order discounts apply to the subtotal after product discounts, and shipping discounts come last.
- Several order discounts. Percentages are all taken from the same subtotal (10% + 20% on $100 leaves $70), then fixed amounts come off.
- One shipping discount. Two shipping discounts never apply to the same order.
- One product discount per item, unless you're on Shopify Plus and both discounts are tagged to stack (see below).
- The shopper gets the best deal. When discounts clash, Shopify applies whichever discount or combination saves the shopper the most.
- Limits. Up to 5 product or order discount codes plus 1 shipping code per order, and up to 25 active automatic discounts.
Worked example: the default cart
Sale, welcome code and free shipping
- Cart
- $120 sweater + 2 × $18 socks + $35 beanie = $191.00, shipping $8.00
- Autumn sale (automatic)
- 20% off products, combines with shipping
- WELCOME10 (code)
- 10% off the order, combines with shipping
- FREESHIP75 (code)
- Free shipping over $75, combines with product and order
The sale and WELCOME10 can't combine, so Shopify compares them. Sale + free shipping saves $38.20 + $8.00 = $46.20. WELCOME10 + free shipping would save $19.10 + $8.00 = $27.10. The shopper pays $152.80 and WELCOME10 is dropped.
2026: several product discounts on one item
Since July 2026, stores on Shopify Plus can let more than one product discount apply to the same item. You tag discounts (for example *seasonal* or *partner*) and set which tags they combine with. The setup has to be reciprocal: each discount must point at the other's tag.
When they stack, percentage discounts are taken from the original price first, then fixed amounts come off the reduced price. In the Two product discounts on one item preset, the $120 sweater gets 20% off ($96) and then $10 off, so it costs $86.
The checker treats the Tagged to stack switch as that reciprocal tag setup. On other plans, leave it off: each item takes only its single best product discount.
What the checker leaves out
- Buy X get Y discounts aren't modeled. Their items generally can't take other product discounts.
- Minimums. Product discount minimums count only the eligible items. Order and shipping minimums are checked against the subtotal after product discounts.
- Customer eligibility, usage limits and dates aren't checked. The tool assumes every discount is live and the shopper entered every code.
- Discounts from apps and Shopify Scripts can follow their own logic, so test them in a real checkout.
- Rounding. Shopify splits amounts across items to the cent, so real totals can differ by a cent or two.
Questions people ask
Why won't my discount code work with my automatic sale?
Usually because one of them isn't set to combine with the other's class. Open each discount in Discounts, check Combinations, and make sure both sides allow it.
Can customers use two discount codes on one order?
Yes, if the discounts are set to combine. Shopify allows up to 5 product or order codes and 1 shipping code per order.
Do two percentage order discounts compound?
No. Both are calculated on the same subtotal, so 10% and 20% off a $100 order leaves $70, not $72.
Can two product discounts apply to the same item?
Only on Shopify Plus, and only when both discounts are tagged to combine with each other. Otherwise each item gets its single best product discount.
Which discount wins when they can't combine?
Shopify applies the discount or combination that gives the shopper the lowest price.
Related tools
Want this builtinto your store?
I'm Emmanuel, a Shopify and WooCommerce developer. If this tool pointed at something you'd rather have fixed for you (a faster store, cleaner product data, a migration, a custom feature), send me a note.
Emmanuel Asika
Shopify & WooCommerce developer, Dublin
I build and fix online stores: new builds, migrations, speed, SEO and the custom bits apps can't do.
Last reviewed 30 September 2026.
Sources: Shopify Help Center: Combining discounts · Shopify Help Center: Amount off discounts · Shopify Changelog: Multiple product discounts on the same item (15 Jul 2026)