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CONVERSION TOOLKIT / GUIDE 03

Quantity breaks & native discounts

Keep per-unit cards, volume tiers and Shopify checkout totals in agreement.

7 min read • Kiln v1.2.0

01Choose a simple tier structure

The demo’s one-pack has no reduction, the two-pack saves 10% per unit and the three-pack saves 20% per unit. Radio cards show the pack size, effective unit price and total savings. Discounts must be based on the selected product variant’s real price and currency precision.

  1. Enable quantity-break blocks on the product template.
  2. Set the tier quantities to 1, 2 and 3, or a sequence appropriate for the product.
  3. Choose the default tier and use restrained labels such as Most popular and Best value.
  4. Keep the add-to-cart quantity synchronised with the checked radio input.

02Configure an enforceable discount

Theme cards communicate a discount; Shopify controls whether the order receives it. Create a compatible automatic product discount or use an eligible discount Function for tiered logic. For rules that overlap on the same products, verify how Shopify selects the best applicable discount rather than assuming all rules stack.

  1. Define qualifying products or collections and the minimum quantity.
  2. Set the reduction for the corresponding tier.
  3. Review discount combinations with order, product and shipping offers.
  4. Place a test order and compare the line-item discount to the product card’s promise.

Native discount capabilities depend on store plan, active apps and current Shopify limits. Use the admin’s available discount types as the source of truth.

03Price calculations and edge cases

Calculate in currency minor units, round consistently and derive pack totals from the final per-unit amount. When a variant changes, update the base price and availability before recalculating tiers. Do not offer a pack larger than available stock if overselling is disabled.

  1. Test zero-decimal currencies and price rounding.
  2. Check subscription selling plans; do not silently combine incompatible offers.
  3. Make unavailable tiers disabled with an explanatory label.
  4. Provide a fieldset legend, native radio inputs and a visible selected state.
Base unit price: $35.00
1 unit × $35.00 = $35.00
2 units × $31.50 = $63.00 (save $7.00)
3 units × $28.00 = $84.00 (save $21.00)

04Troubleshoot a mismatch

If the drawer or checkout price differs, inspect the actual discount allocations in the returned cart and the active discount’s qualifying rules. Check that the cart has the same variant, quantity and selling plan as the card. Clear expired codes, inspect discount combinations and test without unrelated discount apps. Never alter a displayed checkout total to conceal a mismatch.

OFFICIAL PLATFORM REFERENCESShopify: B2B quantity rules and volume pricing Shopify: Combining discounts

Platform requirements checked 24 October 2026. Reconfirm plan-specific availability in Shopify admin.

Need help with your store’s setup?

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