How to Let Customers Build Their Own Bundle on Shopify
Shopify has no built-in way to let customers build their own bundle: its free Bundles app sells fixed sets and multipacks, so the customer can't choose what goes in. To let customers pick, you use a bundle app: you give the bundle one or more collections to choose from, set a rule for each one (such as "pick exactly 3"), set the bundle price, and the app adds the picked items to the cart as one bundle.
This guide covers the decisions that make a build-your-own bundle work: which pick rule to use, when to split the bundle into steps, which price holds up when every customer picks something different, and what happens in the cart, on the order and in your inventory. The examples use Bundly, the app we make, and every Bundly detail comes from how the app works today. To see one live, open the Bundly demo store.
What a build-your-own bundle is
A build-your-own bundle (also called mix-and-match, build-a-box or a custom bundle) is one product with choices inside it. The customer picks the items. You set the rules and the price. Three shapes cover most stores:
One pool. "Pick any 3 candles." One collection, one rule.
Steps. "Pick a cleanser, then a serum, then a moisturizer." One collection for each step, each with its own rule.
Fixed items plus picks. "The gift box is always included. Pick 6 snacks to fill it." You choose some items, and the customer chooses the rest.
In Bundly, you build all three the same way. Add a product or variant, and it goes in every bundle ("Customers receive"). Add a collection, and the customer picks from it ("Customers choose from"). Mix both in any order. In the duvet set below, the duvet cover is always included, the customer picks 2 pillowcases, and the flat sheet is optional.
What Shopify can do without an app
The Shopify Bundles app makes fixed bundles and multipacks. You choose every product, and the customer only chooses variants. There is no "pick any 3". We tested it limit by limit in Shopify Bundles vs Bundly.
A collection plus an automatic discount comes close. Put the eligible products in a collection, then create an "Amount off products" automatic discount that applies to that collection, with the requirement "Minimum quantity of items" set to 3 (Shopify Help Center). Customers add products one by one, and the discount shows up in the cart when they reach 3. It costs nothing, but:
The only rule is "at least". A customer who adds 7 gets the discount on all 7, and nothing can cap the box at 3.
The discount is a percentage or an amount off. There is no set price such as "any 3 for $30".
There is no builder. Nothing shows "2 of 3 picked", and nothing collects the picks in one place.
The items stay separate lines in the cart and on the order. Nothing tells the person who packs the order that 3 of them are one gift box.
If "3 or more, 10% off" is all you need, this method works. Our bundle creation guide shows it step by step. The rest of this page is for everything it can't do.
Pick rules: exactly, at least, up to, between
Every pick needs a rule. Bundly has four. The bundle page shows each one to the customer as a short label under the step title:
Rule in the admin | Example | What the customer sees | Use it for |
|---|---|---|---|
Exact quantity | 3 | "Select 3" | A box with a set number of slots: a 3-candle gift box, a 6-pack. Use it with a fixed price. |
Minimum quantity | 4 | "Select 4 or more" | "4 or more, 10% off", with a percentage discount |
Maximum quantity | 2 | "Select up to 2" ("Optional" for 1) | Add-ons the customer can skip: a greeting card, gift wrap, one extra sample |
Quantity range | 3 to 6 | "Select between 3 and 6" | A box the customer can size, with a percentage discount |
Each rule takes a number from 1 to 2,000.
How the rules work on the bundle page:
The Add to cart button stays off until every step has its minimum. Until then it shows the count, for example "Add to cart (3/4)".
The customer can't go over a maximum. When a step is full and the customer adds another product, it takes the place of the last one picked.
The customer can pick the same product more than once. Each click on "Add to bundle" adds one more. To show a −/+ selector instead, turn on "Show quantity selector for added products" in the theme editor.
For a product with sizes or colours, the button reads "Choose options" and opens a quick view with option buttons or colour swatches. Sold-out variants can't be picked.
Match the rule to the price. With a fixed price, an open rule ("4 or more", "between 3 and 6") makes every extra item free. Use "Exact quantity" with a fixed price.
One pool or several steps
Use one pool when the items are interchangeable: candles, teas, socks, snacks. Use steps when:
the box needs one of each kind (a skincare routine: one cleanser, one serum, one moisturizer);
the kinds cost very different amounts (see the pricing section below);
part of the box is optional ("Add a card: Optional").
In Bundly, each collection component is a step. One step is open at a time. When the customer fills a step, the next one opens and scrolls into view. The "Your bundle" summary lists every pick with its image and a remove button, and on a phone it stays at the bottom of the screen. The picks are saved in the page address, so a reload or a shared link keeps the half-built box.
Each step reads its collection live. When you add a product to the collection, it shows up in the bundle, and you don't edit the bundle. Products show in the collection's sort order, 12 at a time with a "Load more" button (you can set 3 to 249 in the theme editor), so put the products you want picked first at the top of the collection.
Bundly allows up to 128 components in one bundle, and 100 collections in your store across all bundles.
How to price a bundle when every customer picks something different
This is where most build-your-own bundles lose money. Take "pick any 3 candles" from a collection where candles cost $18, $24 or $32. The cheapest box is 3 × $18 = $54 at full price. The most expensive is 3 × $32 = $96. Here is what each pricing option in Bundly does to those two boxes:
Pricing | Cheapest 3 ($54) | Most expensive 3 ($96) |
|---|---|---|
No discount | $54 | $96 |
Percentage discount: 15% | $45.90 (save $8.10) | $81.60 (save $14.40) |
Fixed amount discount: $10 | $44 (save 18.5%) | $86 (save 10.4%) |
Fixed price: $49 | $49 (save 9.3%) | $49 (save 49%) |
Fixed price: $60 | $60, which is $6 more than the candles cost on their own | $60 (save 37.5%) |
What this means:
Percentage discount follows what the customer picks. Every box gets the same share off. It is the safe choice when prices in the pool differ.
Fixed amount discount comes off the whole bundle once, not off each item. Cheap boxes get a larger share off.
Fixed price is one price for any combination. Set it below the cheapest possible box, or some customers will see a bundle price above the price of the items. It works best when every product in the step costs the same. If prices differ, split the pool into steps by price, or use a percentage.
No discount charges the sum of the picks. Use it when the box itself is the value: gift packing, a curated assortment.
While the customer picks, the bundle page shows a live total. You can also show the price before discount and the saving, as "15% off" or "$10 off". With Shopify Markets, a fixed amount or fixed price converts to the customer's currency. For more examples, with data on how hundreds of Shopify stores price their bundles, see our bundle pricing examples.
What happens in the cart, on the order and in your stock
Cart. Bundly adds the picked items, and Shopify's Cart Transform merges them into one bundle line at the bundle price (Shopify: About product bundles).
Order. Shopify keeps the picked products on the order as components of the bundle line. Bundly also writes each pick on the bundle line, numbered: "#1: Fig candle - Large", "#2: Cedar candle × 2". The customer sees them in the cart and at checkout, and the person who packs the order sees exactly what was chosen. This is on by default. Turn it off with "Add bundle contents as line item properties" if your cart already shows the bundle contents. The demo store has it off, so the checkout below shows only Shopify's own list.
Stock. Shopify tracks inventory on the products inside the bundle, not on the bundle. The bundle product shows "Inventory not tracked" in your admin, and that is expected (why).
Products added one by one. With "Automatically detect the bundle in cart" turned on, a customer who adds the right products from their own pages still gets the bundle price.
Limits to know before you build
These come from Shopify and apply to every bundle app that uses Shopify's bundle API:
Subscriptions and pre-orders. Bundles can't be sold with selling plans (Shopify).
Google, Facebook, Instagram, TikTok. App-built bundles can't be published to those channels. Link ads to the bundle page instead (details).
And these are Bundly's own:
Shopify POS. There is no bundle builder in POS yet. Staff can add the products one by one, and with "Automatically detect the bundle in cart" on, Bundly merges them at the bundle price (steps).
Discount codes. Decide if customers can add a code on top of the bundle price (how).
Set it up in Bundly
Install Bundly and run the one-time theme setup. The full walk-through is in our bundle creation guide.
Click Create a bundle. Use Add collection for each step, or Create collection to group products for this bundle. Use Add product or Add variant for items that are always included.
Set each step's rule: Exact quantity, Minimum quantity, Maximum quantity or Quantity range.
Choose the pricing: No discount, Percentage discount, Fixed amount discount or Fixed price.
Save the bundle. Then, under Layout, choose Minimal, Compact or Wide. Compact is made for small mix-and-match bundles. Wide is made for bundles with many items.
Set the status to Active and save.
On the Standard plan, variant filters limit a step to some variants, for example only the small size in a sampler box.
Bundly costs $29 a month (Basic) or $59 a month (Standard), with a 14-day free trial. Build-your-own bundles, steps and all four pricing options are on both plans. Try Bundly on the Shopify App Store.
FAQ
Can I make a build-your-own bundle on Shopify without an app?
Only part of one. A collection with an "Amount off products" automatic discount and a minimum quantity gives "3 or more, X% off". It can't cap the box at 3, set a bundle price, or show the customer a builder, and the items stay separate lines on the order.
Is a mix-and-match bundle the same as a build-your-own bundle?
Yes. Both mean the customer chooses the items from a pool you define. "Build a box" and "custom bundle" mean the same thing.
Can a customer pick the same product twice?
In Bundly, yes. Each click on "Add to bundle" adds one more, up to the step's maximum.
How is inventory tracked for a build-your-own bundle?
On the products inside it. When a customer buys a box with 3 candles, Shopify takes 3 candles out of stock. The bundle product itself has no stock count.
Can I sell a build-your-own bundle as a subscription?
No. Shopify doesn't allow bundles with selling plans, so no bundle app can do this with Shopify's bundle API.
What happens when I add a product to the collection?
It shows up in the bundle on the next page load. Bundly reads the collection live, so you manage the choices the way you manage the collection.