The gift set that did not exist
You sell a candle on its own, and in a gift set with a diffuser and a card. The gift set sells well in December. Someone set it up as its own product with stock of fifty. Meanwhile the candle sells on its own too, and nobody reduced the gift set's number when candle stock ran out. Now there are orders for twelve gift sets and no candles to put in them.
Or it happens the other way: the individual items show in stock but the bundle shows zero, because someone forgot to update its number, so a best seller quietly stops selling.
Why bundles break stock
A bundle is not really a product. It is a recipe: this many of these items, packed together. If the store treats it as a product with its own count, you have two independent figures describing the same physical stock, and they will disagree.
Shopify has added ways to handle bundles, and there are bundle apps, and for many stores those are enough. The trouble starts when bundles interact with other systems. The warehouse sees a bundle SKU it has no stock of. The 3PL cannot pick it. The accounting system does not know what cost to use. Or the bundle has a choice in it, like "pick any three flavours", which multiplies the combinations.
What broken bundles cost
- Oversold bundles, cancelled at the busiest time of year.
- Bundles showing out of stock when all their parts are available.
- Warehouse staff guessing what goes in a bundle, or asking every time.
- Margins that are wrong because the bundle's cost is not the sum of its parts.
- Someone spending time each week adjusting bundle stock by hand.
Seasonal bundles make this worse, because they are created in a hurry right before the period when accuracy matters most.
How we link bundles to their parts
- Define each bundle as a recipe. A list of component SKUs and quantities, stored against the bundle, including options where the customer chooses some of the contents.
- Calculate availability. The bundle's sellable stock is worked out from the scarcest component, so it can never promise more than the parts allow.
- Deduct components on sale. When a bundle order comes in, stock is reduced on each component, not on a separate bundle count.
- Explode the order for fulfilment. The warehouse or 3PL receives the individual parts to pick, with a note that they are packed together, so they never see a SKU they do not stock.
- Carry the cost through. The bundle's cost is the sum of its parts, so margin reports and accounting entries are correct.
- Watch for trouble. When a component runs low and will take a popular bundle out of stock, you get a warning while there is still time to reorder.
| Setup | When it suits |
|---|---|
| Shopify native bundles | Simple fixed bundles, fulfilled in-house |
| A bundle app | Mix-and-match on the storefront with modest stock needs |
| Custom logic via the Admin API | Bundles that must reach a WMS, 3PL or ERP correctly |
We start by checking whether the native features or an app would do the job. We build only where the bundle has to flow into other systems or has rules the tools cannot express.
Bundles that look after themselves
Bundles stop overselling because their stock is derived, not typed. The warehouse picks parts it recognises. Margins are real. Creating a new seasonal bundle becomes a matter of writing its recipe, and stock takes care of itself from there.
When a component is about to run out, you know which bundles it will affect, before a customer finds out.
Could this be happening to you?
- Bundles or gift sets have their own stock number in Shopify.
- You have cancelled bundle orders because a part ran out.
- Your warehouse or 3PL does not recognise bundle SKUs.
- Someone updates bundle stock by hand.
- You are not sure what margin you make on each bundle.