"Spend $50, get a free sample." Standard promotion. In the Shopify admin you create a Buy X get Y discount, set a minimum purchase amount, pick the sample product, apply 100% off. Five minutes of work.

Then nothing happens.

Unless the customer adds the sample to their cart themselves, the discount never fires. This isn't a misconfiguration. Shopify's help center says it directly in the considerations for Buy X get Y discounts:

Customers must add all items to their cart manually. The free or discounted "get" item is never automatically added to the cart.

The automatic discounts page repeats the point. Shopify's discount layer isn't a mechanism for changing what's in the cart. It's a mechanism for distributing markdowns across a cart that's already settled.

Below: why that's true at the API level, what breaks when you try to push the native feature into service anyway, and five real free-gift apps compared on the same axes. Research date September 1, 2026. All prices are USD as listed on the Shopify App Store.

The short version

If you need the gift added to the cart automatically, an app is the only path. This is a structural property of Shopify's discount layer, not a preference. The reasoning is below.

If you can build a flow where customers add the gift themselves, native Buy X get Y is enough. 100% off ("Free") is available natively. You will run into the combination restriction covered below.

If cost is the priority, Sales Motivator ‑ Free Gifts is the outlier: free at 0–30 orders per month, $9.99 to 100, and $19.99 for unlimited monthly orders with no usage fees.

If you need a Japanese admin UI, that narrows to BOGOS or Gift Box. EG Auto, Sales Motivator, and USO are English-only, and their listings state the developers don't offer direct Japanese support.

If you plan to run several gift campaigns concurrently, check the number 25 first. A store can have at most 25 active automatic discounts, and app-generated discounts count toward that total.

What the native discount actually does

Worth being precise about what works, because most people don't trip here.

Buy X get Y takes either a minimum quantity or a minimum purchase amount as the "customer buys" condition, then a quantity, a product or collection, and a discount value for "customer gets." The value can be Percentage, Amount off each, or Free — so 100% off is natively supported.

You can cap the number of times it applies per order, and it works as both a discount code and an automatic discount. Eligibility can target all customers, specific customers, customer segments, or Markets. When the buy and get sets overlap, the lower-priced of the customer's chosen items is the one discounted.

Shopify's native discount types number exactly three: Amount off, Buy X get Y, and Free shipping. The help center directs anyone needing tiered discounts, multi-step logic, or custom eligibility to App Store apps or, on Plus, Checkout Blocks.

Why it can't add the item

This part matters because it determines whether waiting for a future Shopify release is a reasonable strategy. It isn't.

Look at the Shopify Functions Discount API reference. The CartLinesDiscountsGenerateRunResult type can return exactly four operations:

• enteredDiscountCodesAccept — accept an entered discount code
• enteredDiscountCodesReject — reject one with a custom message
• orderDiscountsAdd — apply order-level discounts
• productDiscountsAdd — apply product-level discounts

There is no operation for adding a line to the cart. A Discount Function can only distribute discounts across lines that already exist.

The obvious next thought is Cart Transform Functions. Same answer. Cart Transform does three things: expand a cart line to show the bundled items inside it, merge multiple lines into one representing a bundle, and override the presentation — price, title, image — of existing line items. All three presuppose an existing line. And the lineUpdate and update operations are restricted to development stores and Shopify Plus.

The execution order at checkout confirms the design intent. Cart Transform runs first, then Discount (cart line discounts), then fulfillment constraints and order routing, then delivery, then delivery discounts, then payment customization, then validation. By the time a Discount Function runs, the contents of the cart are already fixed.

To be precise: Shopify doesn't publish a single sentence saying "Functions cannot add cart lines." The conclusion above follows from the absence of such an operation in the schema, combined with the help center's statement that customers must add the item themselves.

What breaks if you push the native feature into service

Suppose you give up on auto-add and instead tell customers to add the gift themselves. Three constraints deserve attention.

Gift products become ineligible for any further product discount. On every plan below Shopify Plus, products participating in a Buy X get Y discount can't receive additional product discounts. Worse, if a customer enters a discount code, the best overall value wins — and the help center notes the outcome plainly: "the Buy X get Y discount is removed and only the discount code applies." Stack a gift promotion on top of a sale and you get behaviour nobody designed. On Shopify Plus, customer-gets items can combine with product discounts on the same line item.

Zero inventory kills the promotion. The help center states that if the inventory of free products drops to zero, they display as sold out and customers can't take advantage of the discount. If your promotional items sit outside inventory tracking, this is where it fails.

Twenty-five active automatic discounts is the ceiling — including app-generated ones. Symmetrically, a store can activate at most 25 discount functions, which all run concurrently and have no knowledge of one another. Stack enough campaigns and you hit this before you hit anything else.

A few more specifications worth internalizing. Discounts apply in order: product, then order (against the post-product-discount subtotal), then shipping. Discounts do not combine automatically — each one needs its Combinations setting configured. A customer can use at most 5 product-or-order codes plus 1 shipping code in a single order. Discounts of $0 or 0% may not behave correctly; the documented recommendation is a minimum of $0.01 or 1%. And a Buy X get Y created in the admin does not apply to checkout's post-purchase page.

What the apps are actually doing

Free-gift apps work in two layers: the storefront side adds the gift line to the cart, and the discount layer zeroes it out. EG Auto Add to Cart Free Gift's listing says it discounts the reward "using the app's Shopify Function or Shopify discount," and its data access section includes Shopify Functions. The Function isn't adding the line — it's marking down a line that something else added.

Which raises the plan question, and here the docs are unambiguous. Functions inside public apps distributed through the Shopify App Store work on stores on any plan. Shopify Plus is required only for custom apps containing Function APIs. Installing a free-gift app doesn't require Plus.

Five apps compared

All figures from Shopify App Store listings on September 1, 2026.

App	Developer	Rating (reviews)	BFS	Free plan	Cheapest paid	Billing axis	Japanese UI
BOGOS: Free Gift Bundle Upsell	BOGOS	5.0 (4,111)	Yes	30 lifetime	$29.99/mo	Gifted order count	Yes
EG Auto Add to Cart Free Gift	506	5.0 (1,008)	Yes	None	$14.99/mo	Number of rules	No
Gift Box	Digismoothie	4.9 (211)	Yes	Dev stores only	$29.99/mo	Monthly order count	Yes
Sales Motivator ‑ Free Gifts	Singleton software	4.9 (148)	Yes	30/month	$9.99/mo	Monthly order count	No
USO: Ultimate Special Offers	Orbit	4.6 (367)	No	10/month	$9/mo + 1%	Usage-based	No

Four observations.

There are three distinct billing axes here. BOGOS charges on "orders that included a free gift." Gift Box and Sales Motivator charge on total monthly store orders. EG Auto charges on how many rules you can run concurrently. USO charges 1% of orders carrying a discount or upsell. Two apps both showing "$30/month" mean completely different things. A store doing 1,000 orders a month with 50 gifted ones is best served by BOGOS's axis; a store applying a gift to every order reads more cleanly on order-count pricing.

Sales Motivator's cost efficiency is the outlier. Free at 0–30 monthly orders, $9.99 at 31–100, and $19.99 for unlimited monthly orders with no usage fees. Compare that to BOGOS Basic at $29.99 for 300 gifted orders ($0.05 each beyond) or Gift Box Growth at $29.99 for 0–100 orders. The gap is not marginal. The tradeoff is English-only, with no direct Japanese support.

"Free plan" means three different things. Sales Motivator (30/month) and USO (10/month) are usable on production stores. BOGOS's free tier is 30 free orders for the lifetime of the account, not per month. Gift Box's free tier is explicitly for trial and development stores. EG Auto has no free plan at all, only a 5-day trial.

Some apps are priced against your Shopify plan. BOGOS Basic at $29.99 is described as "for Shopify Basic stores," Grow at $49.99 for Grow/Shopify/Professional stores, and Plus at $109.99 for Shopify Plus stores. Upgrade Shopify and the app bill rises with it. EG Auto's Enterprise tier at $49.99 is likewise Plus-gated, because its checkout-code gift feature requires Plus.

Notes on individual apps

BOGOS: Free Gift Bundle Upsell

Developed by BOGOS, formerly Free Gifts by Secomapp. Launched December 17, 2014. Rated 5.0 across 4,111 reviews, Built for Shopify. Japanese is among the listed languages.

The free tier covers 30 free orders for the lifetime of the account and includes BOGO, BXGY, gift with purchase, classic bundles, mix and match, volume discounts, Frequently Bought Together, thank-you-page upsell, and real-time analytics — an unusually broad free scope.

Paid: Basic $29.99 (300 free orders/month, $0.05 overage), Grow $49.99 (600), Plus $109.99 (2,000). Annual saves 20%; all paid tiers carry a 7-day trial. Integrations include Checkout, Shopify POS, Shopify Flow, and Headless via Hydrogen.

4,111 reviews is the category leader by a wide margin. The Shopify Flow and Headless support make it the pick when the gift logic needs to reach beyond the standard storefront.

EG Auto Add to Cart Free Gift

Developed by 506, London. Launched December 2, 2019. Rated 5.0 across 1,008 reviews, Built for Shopify. English only, and the listing states the developer doesn't provide direct Japanese support.

No free plan. Standard $14.99 (up to 3 concurrent rules), Unlimited $29.99 (unlimited rules, collection and product-tag triggers, tag/spend/history/B2B targeting, geo-targeting, magic links for email), Enterprise $49.99 (enter a code at checkout to unlock a gift — Shopify Plus only). All tiers get a 5-day trial; annual saves 25%.

The distinguishing property: no cap on monthly orders or revenue. Billing scales only on rule count, so stores with high order volume and few distinct gift campaigns get stable costs. Triggers on cart subtotal, quantity, or specific products; auto-add or popup; start and end scheduling; out-of-stock alerts.

Gift Box

Developed by Digismoothie, Prague. Launched April 9, 2019. Rated 4.9 across 211 reviews, Built for Shopify. Japanese is listed among languages, but the developer doesn't provide direct Japanese support.

Pricing keys off monthly online store orders: Growth $29.99 (0–100), Scale $49.99 (101–500), Advanced $79.99 (501–1,000), with no usage fees. Annual saves 17%; 3-day trial plus a 60-day money-back guarantee. The free plan is for trial and development stores.

Every tier includes the same features — unlimited free gifts, four offer types (spend threshold, specific product, free shipping, BOGO), automatic add to cart, Buy X Get Y, and multi-language support. No feature gating between tiers makes the comparison unusually clean.

Sales Motivator ‑ Free Gifts

Developed by Singleton software, Slovakia. Launched March 30, 2020. Rated 4.9 across 148 reviews, Built for Shopify. English only, no Japanese support.

The free tier covers 0–30 monthly orders and includes unlimited free gifts, automatic add to cart, Buy X Get Y, detailed conditions, multi-language, and chat and email support. Starter $9.99 covers 31–100; Advanced $19.99 is unlimited monthly orders. No usage fees. Paid tiers get a 14-day trial; annual saves 25%.

Integrations include Checkout, Currencies, Markets, Translate & Adapt, and Translations — a set aimed at multi-currency, multi-language operations.

Staying at $19.99 past 100 orders per month is the clear price advantage over the other four. Whether an English-only admin is acceptable is the deciding question.

USO: Ultimate Special Offers

Developed by Orbit, Vancouver. Launched October 28, 2015. Rated 4.6 across 367 reviews. The only app of the five without a Built for Shopify badge.

Free tier: 10 orders per month carrying a discount or upsell. The Ultimate plan is $9/month plus 1% of each order carrying a discount or upsell, capped at $10 per order. 14-day trial.

With nine offer types — BOGO, bundles, upsells, quantity breaks, gifts, goal-based offers — this is a general promotions app, not a dedicated free-gift auto-add tool. It's the only one in this set that lists Shopify POS integration.

The 1% usage fee gets expensive at high average order values. At a $150 AOV with 200 gifted orders per month, 1% is $300. Run the numbers against your own AOV before installing.

Pre-install checklist

• Do you genuinely need automatic cart insertion? If "please add the gift to your cart" works, native Buy X get Y suffices
• Will other sales or discount codes run concurrently with the gift campaign? Below Plus, gift products take no further product discounts
• How will you manage gift inventory? Zero stock stops the promotion
• How many automatic discounts will run at once? The ceiling is 25, app-generated included
• Does the billing axis match your order mix — gifted-order count, total order count, rule count, or percentage?
• Have you modelled cost as order volume grows? USO's 1% in particular scales with AOV
• Are you planning to upgrade your Shopify plan? BOGOS's pricing moves with it
• Is an English-only admin acceptable? Only BOGOS and Gift Box list Japanese, and neither offers direct Japanese support
• Is the free tier monthly or lifetime? BOGOS's is 30 orders lifetime

Bottom line

Four steps, in order:

1. Decide whether auto-add is actually required. If not, skip the app — but verify the combination restrictions and inventory handling first
2. If it is required, accept that an app is the only route. Shopify's discount layer isn't built to add cart lines, and that isn't the kind of thing a release note changes
3. Model the billing axis against your real numbers. Comparing "$29.99/month" against "$29.99/month" will mislead you badly once volume moves
4. During the trial, test the gift alongside a discount code. A gift silently disappearing the moment a code is entered is only discoverable here

App Store pricing, ratings, and badges change. Everything here reflects listings as of September 1, 2026 — verify on each app's page before installing.