Mobile shoppers are impatient. When someone scrolls your product description on their phone and loses sight of the add to cart button, they're one swipe away from leaving. A sticky add to cart bar fixes that — it pins a persistent buy button at the bottom of the screen so shoppers never have to scroll back up to take action.
The difference in conversion rate between stores that have one and stores that don't is especially pronounced on mobile, where screen real estate is limited and attention spans are short. In this guide, you'll learn what a sticky add to cart bar does, why it matters specifically for mobile shoppers, and how to add one to your Shopify store in minutes.
A sticky add to cart bar is a fixed element that stays at the bottom of the screen as users scroll. On mobile, it typically shows the product title, price, and an add to cart button — all visible without any scrolling. Some stores also include a variant selector (size, color) so the shopper can choose options directly from the bar.
On desktop, shoppers often see the entire product page without much scrolling. On mobile, a typical product page requires 4–7 scrolls to get through images, descriptions, reviews, and related products. The add to cart button that's above the fold on desktop is buried on mobile.
Mobile conversion rates on Shopify stores typically run 1–2 percentage points below desktop. The gap isn't because mobile shoppers are less ready to buy — it's because the experience creates more friction. Three common friction points:
Scrolling to find the button. Shoppers who read reviews or product descriptions have to scroll back up to buy. Many don't.
Accidental taps. Small, non-persistent buttons are easy to miss or mis-tap on a touchscreen.
Distraction windows. Mobile users switch apps, receive notifications, and interrupt their session more than desktop users. Every second they can't see the buy button is a second they might leave.
A sticky add to cart bar addresses all three.
You don't need a developer or theme customization to add a sticky add to cart bar. Here's how to do it with Boolean Conversion Kit:
Go to the Shopify App Store and install Boolean Conversion Kit. The sticky add to cart bar is one of 12 built-in conversion tools included in the app.
In your Shopify admin, go to Apps > Boolean Conversion Kit. Find the Sticky Add to Cart Bar tool and toggle it on.
Choose what to display: product title, price, and whether to show a variant selector. You can also set whether the bar appears on mobile only, desktop only, or both. For most stores, mobile-only makes sense — your desktop layout already keeps the button visible.
Match the bar's background color and button color to your theme. Keep the CTA button text short — "Add to Cart" or "Buy Now" works best. Avoid adding secondary links or text that competes with the primary action.
Use your phone or the mobile preview in Shopify to confirm the bar appears at the bottom of your product pages. Save and publish.
Not every element belongs in the sticky bar. Clutter reduces conversions. Keep it to:
Don't add reviews, upsell offers, or multiple buttons. The job of the sticky bar is one thing: make the buy action visible and easy to tap.
Show the bar below the fold. Configure the bar to only appear after the user scrolls past the native add to cart button. If both are visible at the same time, it looks repetitive.
Match your brand. A sticky bar that looks like a foreign element breaks trust. Use your brand's primary button color and keep the styling consistent with your theme.
Test on real devices. The mobile preview in a browser is not the same as using a real iPhone or Android device. Test on both before going live.
Track your mobile conversion rate. Before adding the sticky bar, note your current mobile conversion rate in Shopify Analytics. Check it again 2–3 weeks later to measure the impact.
A sticky add to cart bar is one of the highest-impact, lowest-effort changes you can make to your Shopify store. If you're getting mobile traffic but not mobile sales, this is where to start.
Boolean Conversion Kit includes the sticky add to cart bar along with 11 other conversion tools — countdown timers, trust badges, free shipping bars, and more. Install it free on the Shopify App Store.
