Checkout abandonment rate is the percentage of shoppers who begin the checkout on an online shop but leave before completing payment. If 400 people start checkout in a week and 260 of them pay, 140 abandoned, so the rate is 35%.
It is narrower than cart abandonment rate, which counts everyone who put something in the basket. Basket abandonment includes plenty of browsers who were never close to buying; checkout abandonment isolates people who had decided and then stopped, which makes it the better number for finding problems in the checkout itself.
How checkout abandonment rate is measured
Checkout abandonment rate = (checkouts started − purchases) ÷ checkouts started × 100
In GA4 the two inputs are the begin_checkout and purchase events. A funnel exploration with those two steps, or with the steps in between such as add_shipping_info and add_payment_info, shows the overall rate and the point at which people drop out. Shopify, WooCommerce and most other shop platforms report started and completed checkouts too, usually with fuller counts, because their figures do not depend on the visitor accepting analytics cookies.
Decide whether you are counting sessions or users, and stick with it. A shopper who starts checkout on Monday evening and pays on Wednesday is an abandonment in a session view but not in a user view, so the two can give quite different answers.
Why it matters
Someone who reaches checkout has already been paid for: the ad click, the email, the content that brought them there. Every abandoned checkout is acquisition cost spent with nothing to show for it, so a modest fall in the rate often adds more revenue than an equal rise in traffic, and at lower cost.
The causes usually sit in a handful of places:
- Delivery charges or delivery times that appear only at the last step.
- Being made to create an account before paying, where guest checkout would do.
- Missing the payment methods people expect, such as PayPal, Apple Pay, Google Pay or a buy-now-pay-later option like Klarna or Clearpay.
- The card authentication step, usually an approval in a banking app or a one-time code, failing or timing out.
- Long address forms with no postcode lookup.
- Doubts about returns, or about who the shopper is actually buying from.
Common mistakes
- Trusting a rate built on broken tracking. If customers who pay by PayPal or through a card provider’s verification page never come back to your order confirmation page, the purchase is not recorded and abandonment looks far worse than it is. Payment providers appearing as referral sources in GA4 is the usual sign; a referral exclusion fixes the attribution, but the return to your site still has to happen for the sale to count.
- Duplicate purchase events. A confirmation page that records a purchase on every reload makes the rate look better than it really is.
- Comparing yourself with an industry average. Published averages mix sectors, devices and definitions. Your own trend, split by device and traffic source, is the comparison that tells you something.
- Going straight to reminder emails. They recover some sales, but they treat the symptom. Fix the step people leave at first.
How to act on it
- Check the tracking before the rate: place a test order with each payment method and confirm exactly one purchase event reaches GA4 with the right value.
- Build a funnel from begin_checkout to purchase, broken down by device category. A much higher rate on mobile usually points to form or payment problems on small screens.
- Go through your own checkout on a phone as a new customer and note every surprise: an extra cost, a forced account, a field that rejects a valid postcode.
- Fix the step with the largest drop-off first, then measure for long enough to tell a real change from normal week-to-week movement.
If paid social sends a large share of your checkout traffic, recent abandoners can be shown a reminder through Facebook and Instagram ads for ecommerce, provided they accepted the marketing cookies that build those audiences in the first place.