Quantity breaks vs bundles vs discount codes

All three raise average order value, and they do it by persuading different people to do different things. Picking the wrong one is not a small inefficiency — it is giving margin away to shoppers who were going to buy anyway. The honest version of this comparison is short, so here it is up front.

The one-line answer

Quantity breaks work when someone would plausibly buy more of the same thing. Bundles work when someone would plausibly buy a different, related thing. Discount codes work when the point is the campaign, not the basket.

Most stores need two of the three and use whichever one they installed first for everything.

Quantity breaks

A per-unit price that falls with volume: 1 for $50, 3 for $45 each, 6 for $40 each. The shopper sees a ladder on the product page and decides how far up it to go.

They work for consumables and repeat purchases. Coffee, supplements, skincare, filters, fasteners, printer ink, pet food. Anything where the honest thought is “I will need more of this anyway”. You are not persuading someone to want something new; you are pulling forward a purchase they were going to make later, which is why the conversion is easy and the margin maths is the hard part.

They also work for genuinely stocked-up categories — party supplies, craft materials, trade quantities — where buying one is the unusual behaviour.

🔴 They are the wrong tool for considered, one-per-household purchases. Nobody buys a second mattress because the second one is 15% off. On that catalogue a quantity break is a discount you hand to the handful of people buying two anyway, in exchange for nothing. If your product is furniture, electronics, or anything with a replacement cycle measured in years, this is not your tool and we would rather you knew that before installing anything, ours included.

Bundles

Sell a set: the shampoo with the conditioner, the camera with the bag and the card. The shopper buys across your catalogue rather than deeper into one product.

Bundles win on cross-sell and on discovery. They put a product in front of someone who was not looking for it, which quantity breaks can never do. They also raise the ceiling: a customer who only ever needs one of your hero product can still spend more.

They cost more to run. Someone has to decide which products go together and keep deciding as the catalogue turns over, and a bundle is only as good as that judgement. Some bundle apps also create a synthetic SKU for the set, which is worth checking before you commit — a separate SKU has its own stock count and does not decrement its components.

Discount codes

A code, or an automatic discount, applied for a period or an audience: WELCOME10, a Black Friday sitewide, an email-list exclusive.

Codes win when the discount is the message. They are attributable — you know the newsletter drove the order because the code came from the newsletter. They start and stop on a date. They can be targeted at one audience without touching what everyone else sees. No other mechanism does those three things well.

What they do badly is standing pricing structure. A code is a campaign; running one permanently trains customers to wait for the next one, and codes do not display as a price ladder on the product page, so they persuade nobody who has not already got the code.

Choosing, in practice

Look at your last hundred orders and ask a single question: when someone bought more than one item, were they more of the same product, or different products?

Mostly the same product — quantity breaks, and the ceiling on your AOV is how far up the ladder you can pull people. Mostly different products — bundles, and quantity breaks will underperform however well you build them. A roughly even split is the common answer, and it means both, with quantity breaks on the consumables and bundles on the rest.

Codes sit alongside either. The question there is not which but when, and the answer is: for campaigns, and not as your pricing model.

If you run more than one

Decide explicitly how they stack, because the default is usually “all of them” and that is how a line item ends up below cost. A tier price is already a discount; letting it combine with a sitewide code and a bundle discount compounds three decisions that were each made on their own.

Note too that on Shopify plans other than Plus, only one product discount applies per line item — a platform rule, not an app one. Two product-level mechanisms will not both land on the same item, so decide which one you want to win.