TLDR: Shopify changed how it counts sessions on September 21, 2026. Bots are now filtered out, visits no longer split at midnight UTC, and some pageview-free sessions now count. Your conversion rate may shift even if orders and sales haven’t. Treat September 21 as a new baseline and judge performance on orders and revenue.
Shopify rolled out a change to how it measures sessions between September 21 and 23, 2026, and your sessions, conversion rate and other session-based metrics may look different once it reaches your store.
Shopify is clear that this doesn’t necessarily mean your traffic, orders or customer behaviour changed. The way they are measured has changed, but the actual metric hasn’t.
Three changes to how Shopify counts a session
Bots are out by default
Identified bot sessions are now filtered out of session related reports by default, though reports that support the Human or bot session filter let you switch them back in. But there’s a catch, the Home page and Live View show session data without that filter, so bots are removed there and you can’t change it.
Midnight UTC no longer splits a visit
Sessions now run on continued customer activity rather than ending at midnight UTC, and a session ends after 30 minutes of inactivity. For UK stores, that midnight cut off landed at 1am during BST, right in the late evening browsing window.
Pageview-free journeys now count
Some sessions without a pageview are included, such as a shopper going straight to checkout from a cart link.
Why your Shopify sessions could go up or down
These changes pull in opposite directions. Counting pageview-free sessions can push your session total up, while filtering bots and merging activity that crosses midnight UTC into one session can push it down.
The net effect depends on your traffic mix. A store hammered by scrapers will likely see sessions fall. A store that leans on cart-link campaigns in email or SMS might see them rise. No single percentage applies to everyone.
Conversion rate moves because the denominator moved
Conversion rate is calculated from sessions, so it can shift even when orders and sales stay flat. Fewer sessions from bot filtering lifts it. More sessions from cart links lowers it.
For example, 50,000 sessions and 1,000 orders gives you 2%. Strip 5,000 bot sessions and the same 1,000 orders now reads as 2.2%. Nothing has improved but the maths has changed.
Shopify’s own guidance is that a higher or lower conversion rate after the update isn’t automatically good or bad.
The full list of affected Shopify metrics
According to Shopify, metrics that might change include sessions, conversion rate, add to cart rate, reached checkout rate, checkout conversion rate, bounce rate, pageviews per session, average session duration and online store visitors. Searches are also on the list.
It goes beyond the obvious too. Metrics that attribute orders or customers to sessions can change as well, and so can custom reports that use session data.
Unaffected metrics: orders, sales and customers
Orders, sales and customer counts are not affected by this update. That makes them your fixed reference point.
If session metrics moved but orders, sales and customer counts held steady, the update may explain the gap and your store’s performance may not have changed at all.
Year-on-year comparisons just got harder
Historical data isn’t deleted or reprocessed, but data after the update uses the new method, so comparisons across the change should be treated as a measurement shift.
There’s also a second date to keep in mind. Bot classification only applies to sessions from October 7, 2025 onwards. Anything before that can’t be filtered the same way. Shopify also warns that using the same filter setting still doesn’t make pre-update and post-update sessions directly comparable.
A Black Friday 2026 vs Black Friday 2025 session comparison is unstable on two counts.
What to do this week
- Annotate September 21, 2026 in every dashboard, client report and board pack.
- Reset your baseline: Shopify recommends using post-update data as the new baseline for session-based metrics.
- Match your filters: When comparing periods in reports that support it, confirm both use the same Human or bot session setting.
- Check your apps: If an app pulls session data from Shopify Analytics, the data it receives can change too. That includes CRO tools and reporting integrations.
- Headless stores, check your setup: Filters and session behaviour can differ on some headless storefronts depending on how analytics are implemented.
Pause before you call that A/B test
Anything launched in mid-to-late September now overlaps with a measurement change. A new product page that “lifted conversion by 10%” might owe part of that lift to bots disappearing from the denominator.
Judge recent tests on orders and revenue, or on a test tool with its own consistent session logic. The same applies in reverse: don’t roll back a change because conversion rate dipped during rollout week.
Expect a wider gap with GA4
Shopify and Google Analytics never matched perfectly. They use different session rules, bot detection and consent handling. After this update, expect the gap to shift. Pick one source of truth per metric and stick with it.
This is a cleaner view of real shoppers, which is good news. It just means September 21, 2026 is now a line in your data. Read everything either side of it with that in mind. Need a clearer source of truth when it comes to your data? Connect your Shopify and ecommerce data into ASK BOSCO® and see everything in one place, cleaned and organised. Download the app now.
