Why a Sticky Add-to-Cart Bar Increases Mobile Conversions in Magento 2

On mobile, the Add to Cart button is above the fold for about three seconds. Then the shopper scrolls to read the description, check the specs, or skim reviews — and the one button that actually matters scrolls away with it.

The button that isn't there when you need it

Desktop product pages have room for the buy box to stay visible alongside everything else. Mobile screens don't. The moment a shopper scrolls down to read more about the product — which is often exactly what convinces them to buy — the real Add to Cart button is gone from view. Buying now means scrolling back up, which is a small amount of friction, but friction is exactly what drops off at the margin on mobile.

That's the whole problem in one sentence: the button most likely to convert a ready buyer disappears at the moment the shopper has decided, forcing an extra step that shouldn't exist.

What the module does

Sticky Add to Cart shows a slim bar fixed to the bottom of the screen — product thumbnail, name, price, and an Add to Cart button — that appears once the real Add to Cart button on the page has scrolled out of view. Scroll back up past it, and the sticky bar disappears again, since the real button is now visible and doing its job.

The detail that matters: the sticky bar's button doesn't reimplement add-to-cart logic on its own. It triggers the exact same real form already present on the page. That means configurable and bundle products still correctly require their option selections — size, color, whatever's configured — exactly as if the shopper had clicked the real button. A naive sticky-cart implementation that just fires its own add-to-cart request is a common bug in cheaper alternatives: it either fails silently on a configurable product or adds a product with no options selected at all.

Because it's driving the same form, anything already wired into that form's submit — validation messages, loading states, success behavior — keeps working without the module needing to duplicate it.

Appears only once the real Add to Cart button scrolls out of view — no redundant bar competing with the real one.
Shows thumbnail, name, and price so the shopper always knows what they're about to buy.
Submits through the page's real add-to-cart form, so configurable and bundle option requirements are enforced identically.
Disappears automatically once the shopper scrolls back to the real button.

Keep the buy button one tap away, all the way down the page.

See Sticky Add to Cart — from $19