Add-to-cart rate is the percentage of visits to an online shop in which the shopper adds at least one item to their basket. Many UK retailers label the button “Add to basket”, so you will also hear it called add-to-basket rate; the measure is identical, and Google Analytics 4 records the action as the add_to_cart event whichever wording your button uses.
How add-to-cart rate works
The usual sitewide calculation is sessions that included an add_to_cart, divided by all sessions, multiplied by 100. If a shop has 8,000 sessions in a month and 560 of them include an add to basket, the add-to-cart rate is 7%.
A second, often more useful version works at product level: add-to-basket actions on a product divided by views of that product detail page. If a waterproof jacket is viewed 1,200 times and added to the basket 66 times, its rate is 5.5%. Product-level rates let you compare one page with another, which a sitewide figure cannot.
The metric sits in the middle of the ecommerce funnel: product view, add to basket, begin checkout, purchase. Where it falls tells you where to look. A low add-to-cart rate points at the product page, the price, stock or delivery information, or the quality of the traffic. A healthy add-to-cart rate followed by a high cart abandonment rate points at the basket and checkout instead. In GA4, a funnel exploration built on these events shows the drop between each step.
Why it matters
Add-to-cart rate is an early signal. It reacts to product page changes long before enough purchases accumulate to judge them, which makes it useful for smaller UK shops with modest order volumes. It also helps you separate a traffic problem from a page problem: if paid social visitors add to basket at a fraction of the rate of email subscribers, the issue may be who the ads reach rather than the page.
Delivery costs often decide it. If shoppers cannot see the delivery charge or the free delivery threshold until checkout, some will hesitate before adding anything at all.
Common mistakes
- Comparing sitewide rates across months when the traffic mix has changed, for example after a blog post brought in many casual readers.
- Broken tracking: the event firing twice per click, firing again when the basket page reloads, or not firing on quick-add buttons in category pages.
- Treating add to basket as the goal. Ad campaigns optimised for add-to-cart events can produce plenty of cheap adds from people who never buy.
- Judging against “industry benchmark” figures with no named source, sector or date.
- Ignoring variant problems, such as a size selector that blocks the button without explaining why.
How to act on it
First, check that add_to_cart fires once per genuine add, on every type of button, using GA4’s DebugView. Then segment the rate by device, channel and product. The most useful list is usually products with plenty of views and a low rate, because those pages are already getting attention and failing to convert it.
On those pages, check the basics: clear photos, the price including VAT, delivery cost and timing, stock status, size guidance and returns information. Then make one change at a time and watch the product-level rate. When I run Facebook and Instagram ads for online shops, add-to-cart rate by audience is one of the first diagnostics I look at, because it shows whether the ads or the product pages need attention.