Discount slots and the 25-discount limit
Shopify lets a store run only 25 automatic discounts at once, shared across every app. This is what a slot is, what uses one, and how to stay comfortably under the ceiling.
A "slot" is one of the 25 automatic discounts Shopify lets your store run at the same time. It is a platform limit, not a Stackable one, and it is shared: Shopify's own automatic discounts, this app, and every other discount app you have installed all draw from the same 25. The Discounts screen in Stackable shows how many are in use right now so you are never guessing.
What a slot is
Shopify allows a maximum of 25 automatic discounts to be active at any one time across your whole store. Each live automatic discount uses one slot. When all 25 are in use, Shopify refuses to activate a 26th until one frees up. Because the limit is store-wide, a discount another app is running counts against the same 25 that yours do.
Why the limit exists
Automatic discounts all run independently at checkout, with no knowledge of each other, and Shopify evaluates every active one on every order. The 25-discount ceiling keeps that evaluation fast and predictable for shoppers.
Straight from Shopify
This is Shopify's own platform rule, not a Stackable one, so it applies whether or not you use this app. Shopify's official guidance on the limit and on combining discounts is linked under Related at the foot of this page.
What uses a slot (and what does not)
- Automatic discounts use a slot. Any discount that applies at checkout without the shopper entering anything counts, whether you made it in Stackable, in the Shopify admin, or in another app.
- Scheduled discounts reserve a slot for their active window. Shopify's limit is about overlapping active periods, so a discount scheduled to run next week takes a slot for the time it is live, and a scheduled discount whose dates overlap 25 others cannot be published.
- Discount codes do not use a slot. Code discounts are a separate system with its own, much larger ceiling, so a campaign that hands out codes never eats into your 25 automatic slots.
- Paused, ended, and expired discounts use nothing. The moment a discount stops being active, its slot is free for something else.
Need many deals live at once and running low on slots? Turn a campaign into a code campaign where it makes sense. Code discounts do not count toward the 25, so they are a pressure valve when your automatic slots are full.
How to stay comfortably under the ceiling
Shopify's guidance, and ours, is to keep only the discounts you actually need live at once. A few habits keep you clear of the ceiling:
- Pause or end campaigns you are done with instead of leaving them live. This frees the slot immediately.
- Watch the "Automatic discount slots" card on the Discounts screen. It shows how full the store is and warns you when you are close.
- Remember other apps. If a legacy discount app still has automatic discounts running, they are using slots too. The Discounts screen lists them so you can see the whole picture.
- Prefer one well-targeted campaign over several overlapping ones. Stackable's tiers and combinations often let a single campaign do the work you might otherwise spread across many.
How Stackable helps
Stackable is built to keep you inside the platform limit rather than let you hit it by surprise:
- Each Stackable plan caps how many campaigns can be live at once, sized to leave headroom under the 25-slot ceiling even with other apps installed.
- The Discounts screen shows every automatic discount on your store in one place, grouped by who created it, with a live count of slots used.
- When you are close to full, the slot card flags it so you can free a slot before publishing something new.
- Publishing a campaign that would exceed the limit is caught up front with a clear explanation, not a silent failure at checkout.
Codes are the exception, not a loophole
It is fine to lean on code campaigns to run more deals at once, since they do not use automatic slots. Just remember shoppers have to enter a code for those, so they are not a drop-in replacement for an automatic discount everyone gets at checkout.