From Limits to Flexibility: Voucherify Use Cases with Shopify Discount Functions

Shopify’s built-in promotion engine limits merchants to 25 active automatic discounts and basic logic. But with Shopify Plus or Enterprise (from May 2025) and Discount Functions with network access, you can integrate Voucherify to break through those limits. Voucherify adds real-time, server-side promotion logic — so you can run multiple, complex promotions at once, all tailored to the shopper as they check out.

Each scenario outlines how to set up the promotion in Voucherify, including the type, rules, metadata, and rewards, plus how it connects to Shopify using Functions and the Voucherify API. All logic stays in Voucherify, while Shopify Functions apply the results in real time based on what Voucherify decides.

Use cases for multi-item purchase promotions (BOGO & Quantity Deals) in Shopify

1. Buy for €X get €Y off / Order threshold fixed discount on cart

Voucherify configuration: Order Discount (Amount) + order total amount validation rule.

2. Buy for €X get Y % off / Order threshold % discount on cart

Voucherify configuration: Order Discount (Percent) + order total amount validation rule.

3. Buy X items get €Y off

Voucherify configuration: Order Discount (Amount) + order items quantity validation rule.

4. Buy X items get Y % off

Voucherify configuration: Order Discount (Percent) + order items quantity validation rule.

Shopify integration notes: The Shopify Function calls the Voucherify Validations API with the cart total; Voucherify will only return a discount if the threshold is met. Once the cart qualifies, Voucherify responds with the discount value (e.g., 10% of the cart or a flat €50 off), and the function applies it to the order.

You can use the Voucherify Qualifications API on the storefront to display callouts like “Spend €20 more to get 10% off” when the cart is below the threshold.

5. Buy 3 for 2 / Buy X items get cheapest free

Voucherify configuration: Cart promotion with Product Discount → 100 % on 1 cheapest unit (or order line item) when quantity ≥ 3 (or X).

6. Buy X products get % discount on cheapest Y

Voucherify configuration: Same as above, but the Product Discount percent would be applied to Y items:‍

+ Max units combined for all matched order lines cap

+ “Starting from the cheapest” discount application rule

+ Order items quantity validation rule.

Shopify integration notes: The Shopify Function calls the Voucherify Validations API at checkout to evaluate the cart; Voucherify identifies the cheapest item(s)  and returns a discount(s). The Discount Function then applies a product discount operation to make the cheapest item free (100% off).

7. Buy X product & Y product get % off

Voucherify configuration: Product-specific validation rule that requires both products in the cart + apply a discount to one item, both items or the whole order — Voucherify supports any option.

8. Purchase‑with‑purchase (PWP)

Voucherify configuration: Same as above (rule “item X & item Y in cart”), but Fixed‑price effect on Y.

Shopify integration notes: For combination rules (Buy X & Y), Voucherify’s response will only include a discount if both products are present and the rule is met; otherwise, no discount (or no new price).

Use cases for free gift promotions (GWP) in Shopify

1. GWP – Spend €X get item free

Voucherify configuration: Order total amount validation rule + Reward (free products) effect.

The reward product can be one designated SKU. Voucherify will output that this item is to be granted free once the rule is met.

2. GWP – Buy X item get Y item free

Product-specific validation rule + reward effect (same as above).

Shopify integration notes: Free item promotions require adding an item to the cart at $0. Since Shopify Functions cannot create new line items on their own, the integration typically needs to handle the gift addition. When Voucherify indicates a free item reward (in its validation response), your Shopify storefront or a small app can intercept that and add the free product to the cart (using Shopify’s Cart API) before finalizing the checkout.

3. Free gift selection

Voucherify configuration: This case works similarly to the previous scenario, with the only difference being that a dummy product item or a product collection would need to be defined instead of a predefined free product. Additional logic on your side would need to be implemented to offer a selection of free products when the Voucherify API returns a dummy product or to capture the selected product from the product collection returned by Voucherify.

Shopify integration notes: When the cart qualifies, you’d present a UI for the customer to choose their gift (from the predefined collection). After they choose, add that item to the cart and re-run the Voucherify validation so it recognizes the chosen gift item and returns a 100% discount for it. Essentially, Voucherify can either directly add the item to its calculation or instruct your system that “the customer can choose one free item from group Y”.

The Shopify Function can then apply the free price to whichever item was chosen (since that item will be in the cart).

Use cases for product-specific promotions and segmentation in Shopify

1. Product fixed discount

Voucherify configuration: Item‑level Amount discount campaign scoped to Dynamic Product Collection (e.g., tag = “Cutlery”). See Product-Specific Campaigns.

2. Product percentage discount

Voucherify configuration: Same, but Percent effect.

Shopify integration notes: The integration passes the cart line-item details to Voucherify. Voucherify’s response will include discounts on the specific items (e.g., each eligible product line gets a discount). The Shopify Function will apply a product-level discount operation on only those specific SKUs, leaving other items unaffected.

3. Limit promotions to collections / category

Voucherify configuration: Product validation rule on dynamic collection (product.metadata.category = "Plates"). Any attribute available (through regular data sync or run-time metadata) can be used. For instance, “limit to product category” is essentially a metadata filter (as a Shopify product, category could be a custom field).

Shopify integration notes: The function does not need to know the categories; Voucherify returns a discount only when the rule is passed.

4. Limit promotions to customer groups

Voucherify configuration: Add Audience validation rule (customer.tag = VIP, segment = B2B, etc.). You can restrict any campaign to particular customers or segments. For example, “VIP customers get access to X promotion” or “Only first-time buyers” or “Customer in loyalty tier Gold”. In Voucherify, you achieve this via Audience rules in the validation rules. If Shopify is synced, you can use customer tags or attributes (e.g., a “member” tag or a metadata field like customer.tier = Gold). Create a validation rule, like Customer metadata tier = Gold or Customer tag contains “VIP”. You can also maintain dynamic segments in Voucherify itself (e.g., a segment of emails or IDs) and use “customer belongs to segment” as a rule.

Shopify integration notes: In integration, there’s nothing extra to do – you just ensure the customer’s identifier is sent in the Voucherify API request (typically by customer ID or email), and Voucherify will evaluate the rule. Non-qualifying customers simply won’t get the discount applied (Voucherify returns an error or no discount).

Use cases for member promotions in Shopify

1. Sign‑up as member during checkout and get xx% off your next order

Voucherify configuration: Order Percent Discount + Audience validation rule customer.orders_count = 0 or order.metadata.new_member=true.

Shopify integration notes: This scenario is somewhat unique because the act of signing up occurs during checkout. You need to ensure Voucherify knows the customer is a new sign-up by the time of discount calculation. 

Possible implementation:

• If the customer account is created earlier in the checkout flow (e.g., they log in or sign up at start), then by the time the Function calls Voucherify, the customer record can have an attribute indicating “just signed up” or simply no previous orders.
• If it’s a membership opt-in (not just account creation), you might have a custom checkbox. In that case, when the user checks it, you could set a cart attribute or trigger an API call to Voucherify to mark the customer. A simpler method: include a flag in the Voucherify validation request (e.g., order.metadata.member_signup=true). The Voucherify rule will pick that up and allow the discount.

2. Sign‑up member campaign and get xx% off your next order (voucher)

Voucherify configuration: Configure a Voucherify coupon campaign for this, with the desired discount and any limitations (e.g., valid for 30 days, one-time use, specific product/category). This would likely be a unique codes campaign, so each new member gets a personal code (unique codes give better tracking and one-time enforcement).

Shopify integration notes: When a customer signs up, you can automate the code distribution. For example, use Voucherify’s Publication API to generate & assign a unique code to the new customer. This can be achieved via a Shopify Flow or webhook: new customer account -> trigger a call to Voucherify to publish a code -> email the code to the customer or display it on a thank-you page. Because we are not using native Shopify discount codes directly, the code will need to be redeemed through Voucherify upon usage.

This means when the customer comes back and enters the code at checkout, the Shopify Function will capture that input (Shopify provides the discount code entered as an input to the Functions). The function then calls Voucherify to validate the code in real-time. Voucherify verifies that the code is valid (i.e., not expired, unused, and matches the correct customer if restricted) and returns the discount details (e.g., “10% off cart”). The function applies that discount to the order.

Miscellaneous

1. Free shipping /Free shipping modes promotion

Voucherify configuration: Discount effect Free Shipping + rule(s) for order value / shipping‑method metadata.

2. Call‑out message

Voucherify configuration: Store human‑friendly copy in promotion.metadata.callout. Use Qualifications API to fetch “eligible” & “within‑reach” promos. You can use this to show messages like “You have a 10% off coupon available!” or “Spend $20 more to get free shipping.”

Shopify integration notes: Since the Shopify Function is calling Voucherify at checkout, you can even use its response to display final messages on the checkout page (though Shopify’s checkout UI is somewhat limited to what you can customize). Because Voucherify is the source of truth, you can ensure the message only shows when the promo is active or applicable.

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