The stock answer to the question is to "test it," but simple tests may lead you astray. If you test the presence of cross-sells against a cart without, and without wins, you may conclude that cross-sells don't work. When it may be your choice of Presentation, how you Populate your merchandising zones, and how you Persuade that wasn't working.
Today we'll look at examples of these 3Ps to help you craft a cross-selling test (or re-test) that "works."
Some sites show cross-sells inside a "mini-cart" or interstitial page before reaching the cart (and some in addition to).
An interstitial page is a page between the product page and cart that displays offers or cross-sells.
Though it's near impossible to predict where the fold will be for each customer, designing your cart with hard bars or lines that separate cart contents from other content can "bounce" the user's eye and prevent scrolling. Consider the fold!
Similarly, tabbed content may be overlooked by the user. Make sure you're tracking mouseovers and click through if you use them.
A carousel is an alternative to tabs for showing more cross sells on a page without clutter or "paradox of choice." Not all users will notice the scroll arrows, but some will.
Enabling products to be added to cart without clicking out of the cart can work for certain products.
Finally, ensure your call-to-action does not get lost in the overall design.
Testing the placement of cross-sells is the only way to tell you what works best for your product and within your design context.
They are typically presented horizontally along the bottom or vertically along right hand side, and sometimes both.
Showing suggestions inline demands attention and may be more effective than side or bottom placement, but attachment depends on the relevance of the recommendation to cart contents.
Art.com uses a twist of this, recommending a value-add as a call-to-action button presented inline in the cart.
Placing above cart contents may also get more attention than side or bottom (use your heat mapping tools to verify).
Perhaps the most creative presentation is BeachBody, which bakes the cross-sell into checkout steps. I was unable to capture a screen grab of it without submitting credit card info.
What the cross-sells are are more important than how you present them!
Paradox of choice
Sometimes less is more, so make sure the number of suggestions presented one of the variables you are testing.
If you do throw a lot of things at the wall, it's a good idea to keep them highly relevant to the product(s) in the cart.
Here Amazon is featuring more from this designer. Consider the context - the product in the cart is bathroom decor, for which it is highly likely that the buyer would be interested in matching items. Each product type is different, so you have to use your noggin to configure appropriate associations.
Sometimes drawing from the same product line actually causes confusion, when it is a substitute for the item in the cart. In this example, it would be better to display the warranty and items frequently bought with the item in the cart, rather than the same products, different SKUs.
With fashion items, cross-selling based on "crowdsourcing" (like people who viewed X also viewed Y) may create a similar situation.
Similarly, cross-selling near-product matches like same shoe, different specs (in this case, boot height) may also be sub-optimal. In this case however, it may be intended as an upsell - to remind the customer that a similar, higher priced item in the line is available.
If you don't have much session browsing data to help you personalize recommendations, using default "top sellers" or "you might like" might work, but make sure you're measuring impact of showing random product suggestions vs. none at all, and tracking click through and attachment rates.
Sometimes it's not about the actual suggestions, but the suggestion that one should keep exploring the shop. Victoria's Secret's in the fashion business, with a large and diverse catalog. Showing more items may be a subconscious trigger to keep looking. (Paired with a "$X till free shipping" callout may be even more persuasive).
If you've read this blog for some time, you'll know about the importance of value propositions in persuasive selling.
Musician's Friend uses one in its warranty callout:
Using "you" in your label, like "Recommended for You" and "You might like" is more persuasive than "Similar items" or "We suggest."
Drs. Foster and Smith do even better, hitting the emotional strings with "Your pet might also like."
Creating a little urgency never hurt no one, either. Harry and David's "Today's specials"
Harry and David today's specials triggers that "maybe I don't want to miss this" feeling, and may win higher attachment rates than generic labels.
Blue Nile offers a no-brainer cross-sell (jewelry polish), but also a discount-with-purchase item that may be enticing.
Tests should be conducted on which items are most attractive, and how the offer is presented (red price, subtle, large vs. small thumbnail, interstitial, etc.
Even if your cross-sells are proven to work in the cart, challenge how you do them today with new designs to see if you can squeeze more revenue out of a different approach.