Cross-sell
Definition
A cross-sell suggests products that complement the item a customer is buying: a case with a phone, laces with shoes, a filter with a coffee machine. Unlike an upsell, it adds a second item rather than upgrading the first. Cross-sells work best in the cart and right after purchase, when the main decision is already made.
Why it matters for your store
Cross-selling raises the number of items per order, which is one of the two levers behind average order value. It also helps customers: someone buying a printer needs paper, and a store that reminds them saves a second trip.
Good cross-sells share three traits. They are cheaper than the main item, so the decision is easy. They are clearly connected, so the suggestion makes sense. And they are few, because a strip of twelve products is a catalog, not a suggestion.
Cross-sells pair well with a free shipping threshold. When the cart is just below the threshold, a small complementary item is the natural thing to add.
How Kambloo handles it
Cross-sell relations are set per product in the product form, alongside upsells. The cart drawer shows a short "Add these too" strip built from those relations, and a nightly job adds "frequently bought together" pairs computed from the last 90 days of orders.
The free shipping progress bar sits in the same drawer, so the customer sees both the gap to free shipping and a suggestion that closes it. Tiered discounts and gift thresholds work the same way.
Items added from the suggestion strip are tagged at the line level, and the growth dashboard reports suggestion revenue separately, so you can see whether the cross-sells earn their place.
Questions about Cross-sell
How do I choose which products to cross-sell?
Start with products that are used together and cost less than the main item. Then let order history take over: products that customers actually buy together are the best cross-sell candidates.
Can a cross-sell hurt conversion?
Yes, if it distracts from the checkout or suggests unrelated items. Keep the strip short, relevant, and below the primary checkout button.