Article · Apparel

How does a T-shirt or apparel store offer buy 2 get 1 free when the free item is another size?

By Super Simple Co · Updated 2026-10-30

An apparel store runs buy 2 get 1 free by adding a Buy X, get Y option to its offer in Supr Bundle & Subscription App: Buy quantity 2, Reward quantity 1, Reward discount Free, and Reward products set to Same product they buy. The shopper gets a variant picker for every unit, so a T-shirt can be a medium, a large and a free small, and when prices differ the reward goes to the cheapest unit.

Who this is for: For clothing and T-shirt stores that want a buy 2 get 1 free deal where the free item can be a different size.

The example used here

A T-shirt store sells one tee in three sizes at slightly different prices: small $22, medium $25 and large $28 (the numbers are an illustration, use your own). The offer is "Buy 2, get 1 free". A shopper who picks a medium, a large and a small pays $25 + $28 = $53.00 and the small is free, because it is the cheapest of the three.

Free gift unlocked

20% off a full box

Set it up

In Shopify, open Supr Bundle & Subscription App > Offers and click Create offer. Choose Bundle (or Bundle + Subscription if shoppers can also subscribe).
On Choose a bundle type, filter by Buy X, get Y and pick the Buy one, get one free starting point, or click Start from scratch and add a bundle option of that type.
Set Buy quantity to 2 and Reward quantity to 1.
Set Reward discount to Free.
Set Reward products to Same product they buy, the classic same-SKU offer.
Give the option a Title such as "Buy 2, get 1 free", add a Badge like "Best value" if you want one, and click Save.

The same option type also covers "Buy 2, get 1 at 50% off": change Reward discount to Percentage off.

How the size choice works

On an option that rewards the same product, every unit is its own choice. The shopper gets a variant picker for each unit in the set, so they can take a medium, a large and a free small instead of three copies of whatever the product page happens to have selected. The picker is always shown on these options whenever the product has more than one variant. A product whose only option is Shopify's default "Title" counts as a single variant, so check the tee has real options such as size or colour.

Each row shows its own price, with the price that unit would cost on its own struck through beside it, so the reward reads as a saving. The word printed in place of a price on the free item is yours to change under Design > Labels.

Which unit is free

When the units are not all the same price, the reward goes to the cheapest unit in the set, the same way Shopify's own buy X get Y discount works. That is what the option strikes through and what the shopper is charged, so nobody can drop their most expensive size into the free slot.

Shopper picks	Free unit	Shopper pays
Medium, large, small	Small ($22)	$53.00
Medium, medium, medium	One medium ($25)	$50.00
Large, large, small	Small ($22)	$56.00

If you would rather not explain this at all, price every size the same. Then the free unit is always one of equal value.

What the buyer pays for the other two

The items being bought are always full price. A Buy X, get Y option's whole discount is its reward, so there is no percentage off the buy side the way there is on a quantity break.

If you add a subscription, the subscription discount comes off each unit first and the reward is worked out on that lower price. A 10% subscription discount on three $25 tees makes each $22.50, so the shopper pays 2 x $22.50 = $45.00 rather than $50.00. To keep the deal to one-time orders, click One-time purchase only on the option and turn it on. The checkout also says "This order has a recurring charge for multiple items" for a subscribed buy X get Y, because the option goes into the cart as two lines, the items bought and the items rewarded. The first order and every renewal are charged exactly what the option says.

Rounding, stock and the default

Round prices, the checkbox under Bundle name, charges a whole amount on Buy X, get Y options, so $79.92 becomes $80.00.
An option your stock cannot fill reads Sold out and cannot be selected, for example when fewer than three tees are left.
Click Make default on the option to have the product page open on it.

Questions

Can the free item be a different product, not just a different size?

Yes. Set Reward products to The offer's products, so the shopper chooses their reward from everything the offer covers, or to Specific products you pick. Taking the same reward more than once gives a variant dropdown per unit.

Which unit is free if the sizes cost different amounts?

The cheapest unit in the set. That is both what the option strikes through and what the shopper is charged.

Does the subscription discount apply to a buy 2 get 1 free option?

Yes, it comes off each unit first and the reward is worked out on that price. Use One-time purchase only on the option if you want the deal on one-time orders only.

Why do I see no size pickers on the option?

They only appear when the product has more than one variant. A product whose only product option is Shopify's default Title counts as one variant.

Every setting is covered in the help center: Bundle types: quantity breaks, Buy X Get Y, fixed bundles, and build-a-box.

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