Google Gemini added UTM parameters (tracking tags appended to URLs to identify where a visitor came from) to its cited links starting in early September, then quietly stopped around September 28. The tag in use was utm_source=gemini. Search Engine Roundtable’s Barry Schwartz said on October 30 that he no longer sees them on any Gemini links. For site owners trying to measure AI-referred traffic, that three-week window has now closed.
What happened with Gemini UTM parameters?
According to Search Engine Roundtable (October 30, 2026), Google began appending utm_source=gemini to URLs cited in Gemini AI responses in early September. That behavior lasted roughly three weeks. Around September 28, the UTM tags stopped appearing, and Search Engine Roundtable’s Barry Schwartz said he no longer sees them on any Gemini links.
SEO researcher Natzir (@natzir9) tracked the change closely and shared a graph showing Gemini’s UTM tags grew for three weeks, then vanished overnight. On October 27, 2026, Natzir posted on X that another researcher, @Xyborg, saw the same drop around September 28. John Mueller of Google also commented on Reddit that he had seen the UTM parameters on Gemini links a month or so earlier.
Does any referrer signal survive?
On the desktop web version of Gemini, yes, partially. According to Search Engine Roundtable, Google still passes referrer data (the signal a browser sends to tell a website which page the visitor came from) from the desktop Gemini interface. Natzir said visits arriving with a gemini.google.com referrer stayed flat the whole time, which suggests that signal was not affected by the UTM removal.
The iOS app is a different story entirely. Natzir noted on October 28, 2026 that the Gemini iOS app opens links inside its own WebView (an in-app browser), which sends no referrer signal at all. In GA4 (Google Analytics 4), those visits land as Direct traffic with no identifiable source. The only way to detect them, per Natzir, is to inspect server logs for the GeminiiOS user agent string.
In summary, the current tracking landscape for Gemini-referred traffic looks like this:
- Gemini web (desktop): Referrer data still passes. No UTM tags as of late September.
- Gemini iOS app: No referrer. Traffic lands in GA4 as Direct. Only detectable via server-side user agent logs.
- UTM parameters (
utm_source=gemini): Active from early September to approximately September 28, then removed from Gemini links.
What this means for AI-search visibility
The real issue here is not just a missing tag. It is that Gemini traffic from the iOS app is invisible by default in standard analytics tools, and no one has published how large that share is.
Think of it this way: imagine a customer walks into your store because a friend recommended you. They never mention the friend’s name, pay cash, and leave no contact info. The sale happened, and it was driven by word-of-mouth, but your records will just show “walk-in.” That is roughly what happens when Gemini iOS users click a citation link. The visit is real, but your analytics attribute it to Direct, diluting your understanding of which channels actually drive results.
The three-week UTM window gave marketers a rare moment of clarity: a clean, attributable signal showing which content Gemini was citing and sending traffic to. That window closed around September 28.
In Hingewise’s view, the pattern here signals something worth watching beyond this specific change. AI platforms are inconsistent about attribution by design or by accident, and that inconsistency makes it harder to justify content investment aimed at AI citation. A brand that earns consistent Gemini citations but cannot measure the resulting visits is likely to undervalue that channel in budget decisions.
The checklist below focuses on what site owners can do right now to recover the most attribution possible without waiting for Gemini to re-implement UTM tags.
Before you lose more Gemini traffic attribution: quick checks
- Filter your GA4 Direct traffic segment for sessions that land on pages likely to be cited by AI (listicles, how-tos, FAQ pages) and compare volume before and after September 28.
- Pull your server access logs and search for the GeminiiOS user agent string to surface iOS app visits that GA4 misclassifies as Direct.
- Verify that your analytics setup captures
gemini.google.comas a referrer source, and create a custom channel group for it if it is currently bucketed into “Other.” - If you use a tag manager, consider adding a rule to tag sessions arriving with a Gemini referrer even without a UTM parameter, so historical data stays consistent going forward.
Whether Google re-introduces Gemini UTM parameters in a revised form, expands referrer passing to the iOS app, or leaves attribution fragmented as it stands now is the key variable to watch in the coming weeks.
Source: Search Engine Roundtable, Barry Schwartz, October 30, 2026
Lam Nguyen · Hingewise
This article was drafted with AI assistance from the sources cited above and checked against them before publishing. The "What this means for AI-search visibility" section is Hingewise's editorial analysis, built on the frameworks and positions we use in our GEO work. How we work: Editorial policy.