Gemini dropped its UTM tag after three weeks, and the drop in your reports is a labelling change
Google stopped tagging Gemini's cited links with utm_source=gemini around September 29. Referrer traffic held flat, so a Gemini collapse in your analytics is the tag disappearing. Your visibility did not fall.
Guilherme Hortinha · 2 November 2026
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Google's Gemini stopped adding utm_source=gemini to the links it cites around September 29, 2026, about three weeks after it began tagging them without documentation. PPC Land reported the change on November 1, citing server-log data from search consultant Natzir Turrado. Google has not said why, or whether the tag will return.
What changed
In Turrado's logs, tagged Gemini visits peaked at 83 a day. The next day they fell to 3.
According to his chart, visits with a gemini.google.com referrer stayed flat the whole time.
Desktop clicks still carry that referrer. GA4 files them as referrals, and since May 13, 2026 Google Analytics has had an AI Assistant channel for recognised assistants.
The Gemini iOS app opens links in a WebView and sends no referrer, so GA4 puts those visits in Direct. Turrado says Android traffic landed in Direct in nearly every case.
Read the drop as a label
The referrer series never moved, so the rise and fall in tagged visits came from the labelling. If your Gemini line climbed in September and then collapsed at the end of the month, the collapse is the tag disappearing. Nothing in that data says Gemini cited you less.
The tag did show how big the blind spot is. While it ran, Turrado found between 0.16 and 0.65 Gemini visits with no referrer for every visit that had one, leaving out the iOS app. That works out to 16 to 65 extra visits for every 100 that the referrer caught, and he treats the range as a floor. PPC Land points out the limits: the post gives no site count, no dates for the "normal week", and the daily counts are small.
The ChatGPT episode in October shows why this goes unnoticed. When ChatGPT's tag was missing from October 7 to 16, Turrado's analysis found the channel lost between 68% and 74% of its visits in server logs. The missing visits could not be found in Direct, because Direct's day-to-day swings were larger than the loss.
What to do
Mark September 29 on any Gemini report, and stop comparing tagged visits from before and after it.
Track Gemini through the gemini.google.com referrer, which held steady.
Find app traffic in raw server logs through the GeminiiOS user agent. GA4 will not show it to you.
Measure visibility from citations in Gemini answers. Clicks undercount Gemini by a margin nobody can size yet.
Frequently asked questions
Does Gemini still pass referrer data?+
From the web version, yes. Visits with a gemini.google.com referrer stayed flat while the tag came and went. The Gemini iOS app sends no referrer, so those visits land in Direct in GA4.
Will Google bring the utm_source=gemini tag back?+
Google has not said. It published no documentation when the tag appeared and none when it disappeared, and Search Engine Roundtable's report contains no statement from the company.
How can I find Gemini app visits that land in Direct?+
For iOS, look for the GeminiiOS user agent in raw server logs. According to Turrado, the Android app has no documented user agent of its own, so its traffic is much harder to trace.
Did Gemini traffic really fall at the end of September?+
Turrado's data does not show a fall. Tagged visits went from 83 a day to 3, while referrer visits stayed flat. The drop in tagged visits comes from the label being removed.
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Co-founder & Head of AI Innovation, Index Lab
Guilherme co-founded Index Lab, an AEO/GEO agency that makes brands the answer AI gives across ChatGPT, Gemini and Perplexity, taking clients from zero AI visibility to top recommendations.
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