# Sticky Add to Cart on mobile product pages: +21.46% cart clicks

- Outcome: Won
- Page type: Product page (Ecommerce)
- Elements: Sticky add-to-cart bars
- Test run by: [U-Digital](https://liftarchive.com/practitioners/u-digital/)
- Commentary by: LiftArchive (our analysis, not theirs)
- Original source: https://wingify.com/success-stories/udigital/
- Page: https://liftarchive.com/test/skincare-store-mobile-sticky-add-to-cart/

Locking the Add to Cart button to the bottom of the screen on mobile product pages raised click-through to cart by 21.46%. U-Digital, a Dutch digital agency, ran this A/B test for a Dutch skin care ecommerce store, and it was published as a VWO case study. The test measured clicks to the cart, not completed purchases.

## Result

**+21.46% cart clicks**

- Mobile click-through to cart from product pages: +21.46%.
- About 7,200 visitors took part over roughly 23 days, split evenly between control and variant.
- Purchases and revenue were not reported, so the effect on sales is unknown.

## Control

On mobile product pages, the Add to Cart button sat in its normal place and scrolled out of view as shoppers moved down the page.

## Variant

The Add to Cart button was fixed to the bottom of the screen, so it stayed visible while shoppers scrolled.

## Why it likely won (our reading)

- Shoppers reading reviews or ingredients lower on the page could add the item without scrolling back up.
- A button that stays on screen is a constant, low-effort prompt to act.
- Skincare buyers often read a lot before deciding, so they spend more time away from the original button.

## Caveats

The client is anonymized. The sample was modest at about 7,200 visitors over 23 days, and the metric was clicks to cart rather than orders.

## How to run this test

- Hypothesis: If we keep the Add to Cart button fixed at the bottom of the mobile screen, then more shoppers will click through to the cart because the button is always within reach.
- Primary metric: Mobile click-through to cart from product pages
- Guardrail: Mobile orders per visitor
- Guardrail: Cart abandonment rate
- Guardrail: Accidental add-to-cart removals
- Who should test it: Stores with long mobile product pages where the buy button scrolls away early. It will likely do little if your product pages are short or already put the button near the bottom.

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Credit: U-Digital ran this test and owns the result. Summary and commentary by LiftArchive (https://liftarchive.com/test/skincare-store-mobile-sticky-add-to-cart/).
Usage: Free to use, quote and build on, with credit and a link: name the practitioner or organization that ran the test and link to its LiftArchive page. The results belong to the practitioners who ran and shared them; the summaries and commentary are LiftArchive's.