Google Analytics Changes the Criteria for What Counts as an User Session

Google is making a slight change to what counts as a session for visits measured by Google Analytics. The change is small, but will affect some visits and will most likely alter the data reported for most websites.

"Beginning today, there will be a small change in how sessions are calculated in Google Analytics. We think this update will lead to a clearer understanding of website interactions," Google said.

Until now, Google Analytics would end a session for a visitor in three cases:

- More than 30 minutes have elapsed between pageviews for a single visitor.
- At the end of a day.
- When a visitor closes their browser.

The first two cases remain intact, but the third one has been changed to make it more specific and detailed. A session will end:

- When any traffic source value for the user changes. Traffic source information includes: utm_source, utm_medium, utm_term, utm_content, utm_id, utm_campaign, and gclid.

When any of the events listed happens, the next page view from that visitor will count as a new session.

Google says that the change makes a session more similar to how a visit is defined. Notably, if a user arrives at your site, even within a short time span, from two different sources, for example, once from a search result, the other time from a link on another site, these will count as two different sessions.

This will make it easier to see what traffic comes from where and how different sources generate sessions. Google also says that not counting browser restarts as two different sessions is a more accurate measure.

On the whole, the change may result in an increase in the number of sessions a site sees. However, the change will be of about one percent in most cases, according to Google's own testing.