Set purchase quantity rules
Add minimum, maximum, and multiple-of constraints to a campaign and verify the coordinated checkout result.
Quantity rules constrain what a shopper can purchase. A discount tier changes the benefit earned at a quantity; a quantity constraint can block checkout when the purchase quantity is invalid.
Add a constraint to a campaign
- Open or create a campaign whose Owner kind is Automatic discount or Purchase requirements only, and add a rule.
- Under Purchase requirements, choose Minimum / maximum quantity.
- In Items counted by this requirement, choose All products, Selected items, or Exclude items.
- In Quantity counted by, choose Each variant separately, Across variants of the same product, or Across all eligible items.
- Set at least one of Minimum quantity, Maximum quantity, or Required multiple, and write the matching message under Messages shown at checkout. Each limit you set needs its own message.
- Run the campaign’s checks, then publish and wait for confirmation.
If the rule has conditions, the requirement applies only when they match.
For example, a required multiple of six counted across all eligible items lets different eligible products add up to one six-unit count. Counting each variant separately instead requires each participating variant’s quantity to meet the rule.
Counting behavior
| Cart state | Result |
|---|---|
| No eligible units | The constraint passes |
| Exactly the minimum or maximum | The bound passes |
| An exact permitted multiple | The multiple-of requirement passes |
| Eligible discounted or free units | Units still count |
Gift metadata and a zero price do not exempt a line. Exclude gift products explicitly in the items counted if they should not count toward the constraint.
Publish discounts and guardrails together
A campaign can contain discount rules, quantity rules, or both. In a mixed campaign, the quantity guardrail must be confirmed before the discount is enabled. Disable, archive, expiry, and rollback coordinate both surfaces; a successful discount step alone does not mean the whole operation has finished.
Quantity rules from campaigns sharing a runtime profile contribute to an app-managed validation resource. They do not consume one separate validation owner for every campaign. The campaign’s checks report when the combined capacity or configuration cannot be published.
Check compatibility
- Quantity rules are unavailable in Discount code campaigns and A/B experiments.
- Missing customer history or required external data cannot be treated as evidence that a condition passed.
- These rules do not enforce quantities on POS, Create Order API, order edits, or recurring subscription orders.
Test before launch
Test no eligible items, a quantity below the minimum, each exact bound, a quantity above the maximum, and valid and invalid multiples. Include mixed products when counting across all eligible items, and a gift if gift products remain in scope.
Check the actual checkout message as well as the campaign status. If publishing is still observing, blocked, or recovering, follow Publish and rollback before assuming the requested configuration is live.