Mobile sticky add-to-cart moved to the top: +16.4% conversion
Test run byClean CommitCRO agency
Commentary byLiftArchiveOur analysis, not theirsMoving the mobile sticky add-to-cart bar from the bottom of the screen to the top showed a 16.4% lift in conversion rate.
Clean Commit ran this test for an anonymized Shopify store across 23,114 mobile visitors over 14 days.
The agency says it did not reach statistical significance, so we count it as inconclusive.
- Conversion rate rose 16.4%, with a 98.4% probability of beating the original. Promising, but not significant yet.
- Revenue per visitor rose 13.2%, and orders rose 14.0%.
- Add-to-cart rate rose 5.1%, and bounce rate fell 6.6%.
- Average order value fell 2.7%, so the gain came from more orders, not bigger ones.
- Overall: inconclusive. A strong signal, not proof.
The change
The sticky add-to-cart bar moves from the bottom of the screen to the top.
Simplified mockup drawn by LiftArchive from the shared screenshots.
Control
On mobile product pages, a sticky add-to-cart bar sat at the bottom of the screen as shoppers scrolled.
Variant
The sticky bar moved to the top of the screen and replaced the header and navigation while it was visible. This freed up the bottom of the screen for product content.
Why it likely came out this way
Our reading of the result, not the practitioner's claim.
- With the bottom of the screen clear, shoppers can see more of the product while they scroll.
- The top of the screen is where the header already lives, so a bar there may feel less like an overlay.
- Swapping the header for the bar removes clutter instead of adding another fixed layer.
Caveats: The test ran 14 days on mobile only and did not reach statistical significance, per the agency.
Who ran it
Clean Commit ran this test for a Shopify store (anonymized) and published the results (Clean Commit A/B test library). The numbers are theirs; the summary and commentary on this page are ours.
Read the original case study on Clean Commit →
How to run this test on your store
- Hypothesis
- If we move the mobile sticky add-to-cart bar from the bottom to the top, replacing the header while it shows, then conversion rate will rise because shoppers see more product and still reach the button.
- Primary metric
- Mobile conversion rate
- Guardrails
- Average order value
- Use of navigation and search while the bar shows
- Revenue per visitor
- Who should test it
- Stores that already have a bottom sticky bar on mobile. Run it long enough to reach significance, and watch it if shoppers rely on the header to search or browse.
Questions
Is a top or bottom sticky add-to-cart bar better on mobile?
In this test the top position showed a 16.4% conversion lift, but it was not yet significant.
Test it on your own store before switching.
Does replacing the header with a sticky bar hurt navigation?
It can, since search and menu links are hidden while the bar shows. Track navigation use as a guardrail.
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