[UA] Why Google Ads Clicks and Analytics Sessions don't match in your reports [Legacy]

Advertisers who link their Google Ads and Analytics accounts are able to view data from Google Ads and Analytics together. When you compare Clicks from Google Ads and Sessions from Analytics side by side, you might expect that the numbers match, however, they often don't. There are a number of reasons why this can occur. We'll explore those reasons in this series of articles.

Clicks

When someone clicks on a Google Ads ad, the click is immediately recorded in the Ad-server logs. Most Google Ads ad types charge the advertiser when the click occurs. There are some ad formats where the click is not always the billing event, but we'll explore non-standard cases later on.

Sessions

Before a session is recorded, several things happen:

1. When the click takes place, the browser is pointed to the advertiser's landing page.
2. The advertiser's website then responds to this request and starts to transfer data from the web server to the user's browser.
3. When the browser starts to download the landing page, there may be a request for several files at the same time, including JavaScript, CSS, images, video, audio, etc. The requests for JavaScript include the Analytics tracking code.
4. The JavaScript file (ga.js or analytics.js) must first be downloaded and interpreted by the user's browser.
5. The user's browser/device and security settings must support:
   • Cookies
   • JavaScript
   • Images
   If any of the above are disabled, Analytics may not be able to record a session. Universal Analytics doesn't strictly rely on cookies and users may handle client ID in their own ways.
6. Next, the browser sends a separate request to google-analytics.com, the Analytics servers.
7. Finally, a session is recorded.

The following diagram Figure 1a. illustrates these steps.

The key takeaway here is that the process to record a click is straightforward; however, recording a session involves requirements and checkpoints. The whole process from click to session should happen within seconds, but if latency is introduced at any of these checkpoints, then this can in turn reduce the click-to-session ratio (more clicks than sessions are recorded).

Learn more about how Analytics calculates a session.

Troubleshoot Clicks and Sessions issues

To identify and solve issues with discrepancies between Google Ads Clicks and Analytics Sessions, try this troubleshooter.