Cross-Sell
Cross-selling is the practice of recommending complementary products alongside the one a shopper is already buying, such as a case with a phone or filters with a coffee maker, to raise order value by adding items that genuinely fit the purchase.
Cross-sells work best when the suggestion answers a question the shopper would have asked anyway: what else do I need to use this well. A camera page that surfaces the matching memory card or strap reads as helpful, because the recommendation closes a gap rather than chasing a bigger cart. The strongest placements sit on the product page and in the cart, where intent is already settled and one more relevant item is an easy yes.
The tactic annoys when the link is weak or the volume is high. Padding a checkout with loosely related products, or stacking five pop-ups before a shopper can pay, trains people to dismiss recommendations on sight and can drag conversion down even as it chases order value. Relevance is the whole game: a small set of obviously matched items beats a long list of maybes.
Reviews do quiet work in a cross-sell. A shopper trading up to an add-on they had not planned to buy leans on social proof to justify it, so visible ratings and a few specific reviews on the recommended item make the difference between an ignored suggestion and an accepted one. Pairing cross-sells with products that carry real review coverage tends to convert better than pairing them with unproven items.