Quick answer
On mobile checkout, the discount field can be hidden under the collapsed order summary. The field might not be gone. Customers may just need to tap “Show order summary.”
Symptom
Customers say they cannot find the coupon box on mobile, but the field appears on desktop. They may be landing on checkout with the order summary collapsed.
Most likely causes
- Collapsed order summary. Shopify’s checkout style docs say the mobile order summary and discount field are hidden by default.
- Customer expectation. Shoppers expect the coupon field to be near contact/shipping/payment fields, not hidden above them.
- No active discounts. If no code is active, the field may not appear.
- Shop Pay / account state. Shop Pay can alter what customers see before login.
- Draft order path. Draft order invoice checkouts may not expose the normal field.
Quick checks
- Open checkout on a phone or mobile emulator.
- Tap Show order summary at the top of checkout.
- Confirm the discount/gift card field appears inside the expanded summary.
- Test a normal checkout with an active discount code.
- Repeat with Shop Pay disabled or not selected, if possible.
Theme, app, or code checks
- Do not assume the theme controls this. Shopify checkout layout is separate from normal theme templates.
- If you are on Shopify Plus, review what checkout customization options are available for your checkout configuration.
- For non-Plus stores, the fix may be customer instruction rather than layout control.
- Consider applying important discounts automatically so customers do not need to find the field.
When to stop guessing
If customers keep missing it and you cannot alter checkout layout, stop trying to hack the theme. Use clearer cart messaging, automatic discounts, campaign links, or customer-service instructions.
Prevention checklist
- Test discount campaigns on mobile before sending emails/SMS.
- Use automatic discounts when the promotion should apply to everyone.
- Add cart or announcement-bar copy like “Enter code in checkout order summary.”
- Avoid hiding the entire promotion behind a field many mobile customers cannot see immediately.