What belongs in checkout page recommendations, and what should stay off them?
October 20, 2026
Short answer: A checkout recommendation has one job: add a small, obvious, forgotten item to an order that is already happening. The moment it asks the shopper to think hard, compare options, or leave the flow to browse, it is costing more orders than it can ever add items to.
The forgotten item test
The right checkout item passes a simple test: the shopper plausibly forgot it, it plainly belongs with what they are buying, it needs no size or complex choice, and its price is small against the order total. Batteries for the device, the care product for the garment, the refill for the dispenser are the classic shapes, and they are classics because they work without persuasion.
Anything requiring a size chart, a compatibility investigation, or a style decision belongs on the product page or in a post purchase offer, where the shopper has attention to spend. Checkout is a payment corridor, not a showroom.
Placement that cannot break the order
One recommendation, below the order summary or after the payment step as a one click post purchase addition, is the safe pattern. Carousels, exit overlays, and recommendations inserted between address and payment steps all interrupt the one sequence in the store where interruption is measured directly in lost revenue.
The addition must never reset entered details, change delivery selection silently, or reprice shipping without a clear notice. A shopper who adds a small item and watches the delivery charge jump will remove the item and remember the trick; a store that absorbs or states the effect keeps both the sale and the trust.
What data should choose the item
Use basket based evidence from real orders: what buyers of this basket actually added in other sessions, at a price ratio that keeps the addition small, and filtered for stock and margin so the offer never promotes a problem product. One evidence based item beats a personalised rail of guesses at this step, because the shopper's patience for relevance testing is zero at checkout.
Suppress aggressively: no offers on gift orders where an addition could confuse the recipient, none where the item is already in the basket in another form, and none when the order is already large or complex. Restraint is the feature that makes the offers that do appear perform.
Post purchase offers move the risk to a safer place
An offer shown after payment, fulfilled onto the same shipment where possible, gets the shopper's full attention with zero abandonment risk to the completed order. For anything beyond the smallest forgotten item, this is usually the better home, and comparing checkout versus post purchase placement for the same product is a test every store can run.
Be honest about fulfilment: if the addition ships separately or later, say so on the offer. A surprise second parcel with a second delivery window converts a successful cross sell into a support contact surprisingly often.
Measure orders saved, not just items added
Judge checkout recommendations on net order value after abandonment effects, not on attach rate alone. A module that adds an item to four orders in a hundred while costing two completed orders is a losing machine reporting a winning metric, and only the combined view shows it.
Review the chosen items monthly. Relevance rots as baskets and seasons change, and yesterday's perfect forgotten item becomes today's puzzling suggestion, quietly training shoppers to ignore the module altogether.
Keep reading: How should recommendation ranking weigh margin and stock levels?, How does visual search change how shoppers find products?, and How can recommendations protect discovery of new and niche products? cover the nearby cases in this series.
Frequently asked questions
What is the safest kind of checkout recommendation?
A single small item the shopper plausibly forgot, plainly connected to the basket, needing no size or complex choice, priced small against the order total. Batteries, refills, and care products are the classic shapes.
Where should checkout recommendations be placed?
Below the order summary, or as a one click post purchase offer after payment. Never between address and payment steps, and never in overlays or carousels that interrupt the payment sequence.
Why are post purchase offers often better than checkout offers?
Because they cannot cause abandonment of a completed order, and the shopper can give them full attention. Anything larger than a tiny forgotten item usually performs better and safer after payment.
How should checkout recommendations be judged?
On net order value after abandonment, not attach rate alone. A module that adds items to some orders while losing others can be a net loss reporting a positive metric.