How to Choose Frequently Bought Together Products on Shopify

Choose frequently bought together products that complete the use of the main product, cost clearly less than it, and really do turn up in the same orders. Let your order data propose the pairs, then edit the list by hand before anything goes on the page. This guide covers where the pairs come from, how to tell a complement from a substitute, how the prices should relate, where the block belongs and how often to revisit it.

Should you use order data or choose pairs by hand?

Both, in that order. Order data shows what customers actually combine; your judgement removes the pairs that are true but useless.

To find pairs in the data, export your orders, take every order containing the main product and count which other products appear alongside it. Then filter:

• Remove the bestseller effect. Your most popular product appears beside everything simply because it is in so many orders. A good partner is one that shows up with this product more than it shows up in general.
• Remove promotion residue. If two products were sold together in a past campaign, the data will pair them long after the reason has gone.
• Ignore thin evidence. A pair seen in a handful of orders is an anecdote.

Manual choice takes over where data cannot help: new products with no history, small catalogues with few orders, and products whose obvious partner has only just been added to the range. In those cases ask what the customer will need on the day the parcel arrives.

What makes a good pairing?

A complement: something used with the main product, not in place of it. The test is whether a customer would reasonably use both together.

• Complement: a tent and a groundsheet, a razor and blades, a notebook and a pen.
• Substitute: a tent and a different tent.

Substitutes do damage in this slot. Showing an alternative beside the add-to-cart button reopens a choice the shopper had already made, and some will leave to think about it. Alternatives belong in a comparison or 'similar products' section further down the page. The distinction is set out in upsell vs cross-sell vs bundle.

The strongest partners are the ones that prevent disappointment: the cable that is not in the box, the bulb the lamp does not include, the cleaner the material needs.

How should the prices relate?

The partner products should cost clearly less than the main one. The shopper came to buy the main product and has accepted its price; the additions should be small enough to accept without starting a second decision.

Say a store sells a camera bag for $80. As example figures, a $12 strap and a $9 rain cover sit comfortably beside it: the set comes to $101 and the bag is still the main purchase. A $70 lens case in the same slot nearly doubles the total and becomes a purchase of its own.

Show the total for the whole set, updated as items are ticked or unticked.

How many products should the set include?

The main product plus one or two partners. Each extra item adds price and reading, and the block has to be understood at a glance. If four things all belong with the product, choose the two that are most often needed and leave the others for the cart or a follow-up email.

How should adding the set work?

With one action. A single button adds everything selected, and each partner has a checkbox so the shopper can drop one without losing the others.

Details that decide whether the block gets used:

• Variants. If a partner comes in sizes or colours, the shopper must be able to choose without leaving the page.
• Stock. A partner that is sold out should disappear from the set, not block the button.
• Price at checkout. If the set carries a discount, it has to be applied automatically. A set does not need a discount to be worth showing; convenience is the offer.

For extras that are options on the product itself, such as a refill or gift wrap, a checkbox add-on is the closer fit; see add-on upsells on the product page.

Where should the block go on the product page?

Near the add-to-cart button, and below it. That is where the decision happens, so the suggestion is seen at the moment it is relevant.

• Keep the main button above the block. Nothing should push the primary action down the screen, least of all on a phone.
• Place it before long descriptions, reviews and specifications. Further down, only the most committed readers will reach it.
• Use one block per page. A frequently bought together set, a quantity break and a bundle on the same product compete with each other.

Marka Bundles & Upsells includes frequently bought together as one of its offer types. It is shown through an app block that you add and position in the Shopify theme editor, so placement needs no theme code changes.

How often should you refresh the pairs?

Whenever the season, the range or the stock changes, and on a fixed date at least a few times a year. Pairs go stale quietly: the partner is discontinued, a better accessory launches, or winter stock is still being suggested in spring.

At each review:

1. Remove partners that are out of stock or being wound down.
2. Re-run the order count for your top products.
3. Add partners for anything launched since the last review.
4. Check how often each set is added, and replace the weakest. The measure to use is attach rate, explained in our guide to bundle metrics.

A short checklist

1. Pull co-purchase counts for each main product from your orders.
2. Discount the bestseller effect and old promotions.
3. Keep only complements; move substitutes elsewhere on the page.
4. Choose partners that cost clearly less than the main product.
5. Limit the set to one or two partners, added with one button.
6. Place the block just below add to cart.
7. Put a review date in the calendar.

Frequently bought together is one of several ways to raise order value, and our guide to Shopify bundle types compares it with the rest. To put a curated set on your product pages, start with Marka Bundles & Upsells.