Short Answer
A discount applies at checkout only when every rule on it passes at that moment. Open the discount in Discounts and check its start and end dates, its minimum order amount, and its eligibility. If a second discount is meant to apply to the same order, check the Combinations section on both.
The discount is in your list, the cart is full, and the total does not move. A discount is a set of rules, and checkout applies it only when the cart, the customer and the date all match those rules at that moment. The rule that fails is one you can read in the discount's own settings, so the fix starts there.
The causes below are the ones you can check in Shopify Admin yourself, without contacting support. Each cause comes with a way to tell it is yours, and the fix section names the setting to open. A combinations problem gets one paragraph here, with a link to the page that covers it in full.
Why It Happens
The discount is not active yet, or it has ended
Start and end times follow your store's time zone. A discount outside its window does not apply.
How to tell: the start date is in the future, or the end time has passed.
The cart does not meet the minimum order amount
A discount code can require a minimum order amount. A cart below that amount gets no discount.
How to tell: the cart is under the minimum, and a larger cart gets the discount.
The customer or product is not on the eligibility list
A discount can be limited to certain customers, products, collections or variants. A buyer or item outside that limit gets no discount.
How to tell: the buyer is not in the customer list, or the cart item is outside the product settings.
A second discount is taking the slot
Two discounts apply to one order only when each one's Combinations setting allows it. Otherwise the best discount for the cart applies, which may not be the one you expected. Can a discount code and an automatic discount work together? has the full rules.
How to tell: the discount you expected is not the one applying.
An automatic discount's requirements are not met
An automatic discount has no code. It applies in the cart and at checkout when its eligibility conditions are met.
How to tell: an eligible item is missing from the cart, or the buyer falls outside the eligibility conditions.
How to Fix It
If the dates are the problem
- From your Shopify admin, go to Discounts, then open the discount.
- Check the start date and, if one is set, the end date. Times follow the time zone selected in your Shopify admin.
- Save the change, then test the discount on the storefront.
If the cart misses the minimum
- Open the discount and check its minimum order amount.
- Add items to a test cart until it passes that amount, then apply the code as a buyer would.
If the customer or product is not eligible
- Open the discount and find the Eligibility section.
- Check which customers can use it, then which products, collections or variants it applies to.
- Keep the limit in mind: a discount code can apply to up to 100 specific customers, products and variants.
If a second discount is taking the slot
- Open the discount that should apply and find the Combinations section.
- Select the discount classes it can combine with, then check the other discount the same way.
- Keep the per-order limits in mind: an order can use up to 5 product or order discount codes and 1 shipping discount code.
If it is an automatic discount
- From your Shopify admin, go to Discounts and open the automatic discount.
- Read its requirements against your test cart. Customers need to add all eligible items to their cart for it to apply correctly.
- There is no code to enter, so the test is the cart and its eligibility settings.
How to Stop It Happening Next Time
Start with the checks Shopify already gives you. Before a discount goes live, set its start and end dates and confirm them against your store's time zone. Then test it on the storefront with a cart that meets the minimum and the eligibility settings, and write down what happened. If two discounts should apply to the same order, check the Combinations section on both before launch.
PromoOS starts and ends each promo you set up in it on its date. It also flags conflicts between those promos when you save them. It does not test a checkout, so the test cart above is still the step that confirms a discount works. You can start and end your promos on time with a walkthrough in PromoOS.
Key Takeaways
- A discount applies at checkout only when every rule on it passes at that moment.
- Check the start and end dates first. Times follow your store's time zone.
- Then check the minimum order amount and the eligibility settings.
- When two discounts should apply together, check the Combinations section on both.