What Is Sticky Add to Cart? Uses and Limits

How a Sticky Add to Cart Bar Works

On a long product page, the main add to cart button sits near the top, by the photos and price. Scroll down to read reviews or the size chart, and it's gone. A sticky button fills that gap. You'll also hear it called a sticky add to cart bar, or sticky ATC for short.

Most versions show the product name and the button. Many also show a small photo, the price and a size or color picker. On phones, the bar often sits at the bottom of the screen, close to the shopper's thumb.

It's still a call to action (CTA), the button that tells a shopper what to do next. The only new part is that it follows them down the page.

Sticky Add to Cart on Shopify

Some Shopify themes come with a sticky add to cart bar as a built-in option. If yours doesn't, you can add one with an app or with custom theme code. Either way, try it on a real phone before you trust it.

Don't expect too much from it, though. In our visitor data from 958 Shopify stores, 6.72% of product views led to an add to cart. So on most views, nobody taps any add button, pinned or not. The bar makes adding easier, but it doesn't give anyone a reason to want the product. Want to see where it sits next to photos, reviews and pricing? Read our guide to sticky add to cart and product page conversion.

Bar Taps vs Real Extra Adds

Example: a shoe store splits its traffic

For one month, half the store's visitors see a sticky bar and half don't. That's an A/B test. Each half gets 2,000 product views. The numbers are made up.

With the bar: 150 adds to cart. 60 of them came through the bar.
Without the bar: 136 adds to cart.

The bar's own report says 60 adds. The real difference is 14 (150 − 136). Most of those 60 shoppers would have scrolled back up and used the main button anyway.

Even the 14 may be luck. With only 2,000 views on each side, a gap that small can show up by chance. So check for statistical significance before you decide. And compare orders too, since an add isn't a sale.

When a Sticky Button Doesn't Help

Short pages. If the main button never leaves the screen, a second one adds nothing.
Skipped options. Products with sizes or colors need a choice first. A well-built bar shows a picker or scrolls the shopper back up. A sloppy one may just add whatever option was set by default, and then the wrong size ships.
A crowded phone screen. Your screen may already have a sticky header, a chat bubble and a cookie banner around the edges. Put a bar on top of that and together they can cover the product, or each other.

Myth: A Button in View Makes People Buy

A sticky button saves a scroll for someone who's already made up their mind. It can't answer the questions that stop everyone else, like price, shipping cost, fit or trust. Some of those are friction in the buying process, and some are about desire. A pinned button fixes neither. Our guide to dedicated buyers and walk-away customers explains why these two groups need different things.

Related Terms

Add to Cart (ATC): the tap that puts an item in the cart.
Add to Cart Rate: the share of visits or views that end in an add.
Product Detail Page (PDP): the page where a sticky bar usually lives.
Quick Add: a button that adds items right from a collection page.
Cart Drawer: a side cart that slides in once an item is added.
Conversion Rate Optimization (CRO): testing changes that turn more visits into orders.