Group price rules decide how shipping cost is allocated when a single order is split across multiple delivery groups in checkout — for example, when items ship from different warehouses or follow different fulfillment paths.

Without a group price rule, each delivery group charges its own shipping fee, and the shopper sees multiple charges. With a group price rule, the cost is allocated intelligently — typically one group pays full price, and the others are reduced (often to zero) — so the shopper isn't charged multiple times for shipping the same order.

Group price rules sit alongside regular Price rules in the same carrier product configuration. While Price Rules adjust the price within a carrier product based on cart conditions, group price rules adjust prices across groups in a split checkout.

Use group price rules when your checkout produces split orders — meaning a single cart that spans multiple delivery groups. Common scenarios:

If your orders never split across groups, group price rules don't apply — regular Price Rules cover everything.

There are two group price rule strategies. Pick the one that matches your commercial logic.

"Pay for the most expensive option, everything else is free."

The most expensive shipping option across all groups keeps its full price. Every other group's shipping is reduced (typically to zero). In split checkout, only one group pays for shipping.

Best when: you want shoppers to pay one shipping fee total, regardless of how many groups the order is split into.

"Pay once per product type, with awareness of relative pricing."

Each unique shipping option is charged once at its first occurrence. Later duplicates of the same option are reduced to zero. The rule also accounts for what happens if the shopper changes their selection — making sure pricing stays consistent as they adjust the cart.

Best when: you want shoppers to pay once per shipping option type, even if the same option appears across multiple groups.

A retailer with split warehouses wants the shopper to pay only the most expensive shipping option chosen, regardless of how many groups the order spans.

Strategy: Discount all but max
​Result: The most expensive option keeps its price; all other groups → 0.

A retailer ships the same product from multiple warehouses. The shopper picks the same shipping method for both. The retailer wants to charge for that shipping method once.

Strategy: Reduce price when more expensive product selected
​Result: The first occurrence of each shipping option keeps its price; duplicates → 0.

A retailer wants every delivery group to charge full shipping (no allocation logic).

Strategy: No group price rule set
​Result: Each group charges its own shipping fee from regular price rules.

Q: When are group price rules applied?
A: Only in split checkout — when the order spans multiple delivery groups. If everything ships in one group, regular Price rules govern the price.

Q: Can I combine both strategies on the same carrier product?
A: No. Each carrier product uses one strategy at a time.

Q: Can I add conditions (cart value, voucher, etc.) to a group price rule?
A: No. Group price rules are strategy-only. For condition-based pricing, use regular Price Rules.

Q: Do group price rules affect the carrier base price?
A: No. Group price rules adjust the price after regular Price Rules and Base Price are calculated. They allocate cost across groups, not within a single group.

Q: What happens if I don't set a group price rule?
A: Each group charges independently using its regular Price Rules. The shopper sees a separate shipping fee per group.

Q: How does "Discount all but max" handle ties?
A: When two groups have the same shipping price, the lower-indexed group keeps its price; the others are reduced.