Gemini traffic: Google now tags its links - but the rules are undocumented

Search Engine Journal reported that Google has added UTM parameters to outgoing links in Gemini, its AI assistant, so that site owners can more accurately see which visits came from it. A UTM parameter is a small label added to the end of a web address that tells your analytics where a visitor came from. That sounds like plumbing, and it is. But for anyone who has wondered whether AI assistants are sending them customers, it is the plumbing that decides whether the answer shows up in your reports at all.

Gemini now labels the visitors it sends you

Users spotted the change before Google said anything formal. According to Search Engine Journal, someone on Reddit started a discussion after noticing that Gemini links now carried UTM tags, describing the behaviour as very new, roughly 24 hours old, and comparing it to the way ChatGPT already tags its links.

Mueller, from Google, replied in that thread: "Nice. I see it too. Doesn't Gemini have a referrer too though? I thought you could already track them." Search Engine Journal ran that exchange under a heading saying Google confirms UTM is on Gemini links. Strictly, what the quote shows is a Google employee seeing the same thing users saw. The report does not cite a Google announcement or help page.

Search Engine Journal says the practical result is that site owners can now more accurately track how much traffic Gemini is sending them, instead of guessing. The publication also argues that better attribution lets businesses compare AI-referred visitors across different AI assistants and against traditional search, and justify spending on AI channels with real numbers.

Why AI visits have been hiding in direct traffic

Search Engine Journal explains the problem plainly. Traffic from AI chatbots like Gemini can show up as "direct" in analytics tools such as GA4, Google Analytics 4. Direct is the fallback bucket, used when there is no referrer and no UTM data to tie a visit to where it came from.

Think of it like a patient who arrives at a clinic with a referral note, compared with one who walks in and says nothing when asked how they heard about you. Both are real patients. Only one tells you who is sending people your way. A UTM tag is the referral note, and it travels with the visitor.

If an assistant was recommending your business and those visits landed in direct, your reports would make that channel look like it did not exist. You might have credited the visit to your sign, your truck, a returning customer or word of mouth, when it actually started in a chat window.

The mobile app is where the trail went cold

Mueller's question was fair: Gemini already passes a referrer, the other signal analytics tools use to see where a visit came from. A Reddit user called CrawlWarden answered it, and it is worth being clear that what follows is that user's account, not a Google statement.

CrawlWarden wrote that the referrer "mostly survives on desktop web only," that reported pass through from the Gemini mobile app "runs around 9 percent," and that "Android assistant invocations strip it entirely, so a large share of that traffic has been landing in Direct instead of GA4's ai assistant medium." The same user added that "a UTM survives the in app webview and shows up in raw server logs too, which is why this matters more than it looks even though the referrer technically already existed."

Mueller replied: "If someone has more information on what happens with the referrer (ideally with something I can reproduce), I'm happy to forward that to the team. It would be great to have these retained (in addition to the UTM-tagging)."

The phone matters because of scale. Google's own blog said on August 11, 2026 that the Gemini app had passed 1 billion monthly users, that 63% of users now talk directly to Gemini by voice, and that it has more than 100 million active users on iOS. The same post says Gemini can automate actions across more than 40 popular Android apps. If CrawlWarden's figures are close to right, the visits most likely to lose their trail are the ones that start on a phone, which is where many people look for a nearby clinic, contractor or store.

Why this lands as AI answers take more of search

Search Engine Journal notes the move comes amid increasing frustration at Google over the shrinking traffic Search sends to websites because of AI Search and Gemini. Other reporting this week shows why measurement matters more each month.

Barry Schwartz of Search Engine Roundtable reported on September 30, 2026 that Google is showing AI Overviews, its AI-written summaries at the top or middle of results, for many large brand names. Chris Long posted on X that 93% of the brands he tested had AI Overviews appearing, a test Schwartz described as covering only about 100 brands. DemandSphere then posted data saying AI Overviews on branded queries tripled in September.

Separately, Schwartz reported that Glenn Gabe saw an AI Overview listing an entire Raiders roster during a game, something Gabe wrote had never shown up for him before. Neither story is about Gemini links, but both describe the same direction: more questions answered by Google's AI before anyone clicks through to a website.

ChatGPT is the other large referrer. TechCrunch reported that OpenAI recently announced ChatGPT had reached a billion monthly users, and an OpenAI engineering post dated September 11, 2026 says its products are used by over 1 billion people each week. With two assistants of that size answering questions, being able to separate their visits from everything else is the starting point for knowing whether AI deserves any of your time or budget.

Google has not documented when the tags appear

The other side: Search Engine Journal says Google's implementation is undocumented, so it is unknown under what circumstances Gemini adds the tags. The publication guesses they may appear when Gemini presents answers that directly reference a website, but says nobody knows for sure until Google documents the behaviour. For comparison, according to Search Engine Journal, ChatGPT adds UTM parameters only to links in answers grounded in web sources, not to information that comes from its training data. If Gemini works the same way, some mentions of your business would still arrive untagged. The report also does not publish the exact tag values Gemini uses, so there is no documented label to filter on yet. The referrer problem CrawlWarden described is one user's claim, which Mueller asked to be able to reproduce, and Google has not said whether it will change anything. Until Google writes this down, nobody can say whether the Gemini number in your reports is the whole story or only part of it.

What a business owner can actually do this week

You do not need to change anything on your website. According to Search Engine Journal, the tags are added by Google to Gemini's outgoing links, so the work happens on Google's side. What you can do is make sure you notice the result.

• If you use GA4, check your traffic acquisition report, broken down by source and medium, over the next few weeks for new entries that mention Gemini.
• Write down your current level of direct traffic today, so you have something to compare against as tagged Gemini visits start to appear.
• If someone manages your website or hosting, ask them to look for Gemini tags in your server logs as well, since CrawlWarden says the UTM shows up there too.
• Once you have a few weeks of data, compare Gemini against ChatGPT and against ordinary Google search, which is the kind of side by side comparison Search Engine Journal says this change makes possible.

Do not read much into the first few days. The Reddit user who spotted the tags described them as about a day old, and Google has published nothing about how widely they are switched on.

Bottom line

Gemini is now leaving a label on at least some of the visits it sends to websites, which turns a guess into a number you can look at. It is a small, unannounced change, reported by Search Engine Journal and noticed by Google's Mueller in a Reddit thread, not launched with a press release.

The change costs you nothing and requires no work, but the number is only useful if you start watching it now and remember that Google has not said how complete it is. When a new customer tells you they found you online, do you know which assistant sent them?