Fewer than half of the top 100 mentioned brands also showed up in the matching top 100 citation lists, on average, in every month Semrush measured. That single stat, from Semrush's "2026 AI Visibility Index" across 22 categories and four AI platforms, should make anyone trusting one dashboard number a little nervous. Your AI visibility score is probably blending two different problems into one tidy figure.

What's the difference between a mention and a citation?

The report splits AI visibility into two metrics. A mention means the brand appears in the answer. A citation means a domain appears as a source. They can sit worlds apart.

Ford is the exhibit. In the U.S. in July, Ford appeared inside all four top-100 mention lists. Its citation rankings, meanwhile, were 1,055th on ChatGPT, 1,146th on Gemini, 1,320th on AI Mode, and 748th on AI Overviews. Other people's pages are carrying the brand.

The reverse also happens. In U.S. Finance on ChatGPT, Investing.com ranked seventh among cited domains but only 50th among mentioned brands. It supplies the evidence; the answer itself is where it's weak. Using the same content tactic for both situations misses the point entirely.

Does the platform change the picture?

Yes, considerably. Gemini mentioned more distinct brands per answer than ChatGPT in every month measured in the U.S. ChatGPT included the most source entries per answer, while Gemini included the fewest.

Their source diets differ too:

• News and information sites led ChatGPT citations in the U.S.
• AI Overviews leaned on streaming, business software, online learning and medical-reference sites.
• AI Mode concentrated citation weight among a smaller group of leading domains.

AI Overviews stood apart most sharply. Its leading brand mentions overlapped less with the other three platforms than any other pairing, in every month measured, and its source overlap with ChatGPT was the lowest. A strong ChatGPT result tells you almost nothing about AI Overviews. If customers use several bots, find out which platform has the gap before spending money to close it.

The U.K. grocery aisle makes the same point. Tesco and Asda both ranked top 100 for mentions on all four platforms. On ChatGPT, Tesco ranked 25th among cited domains while Asda sat at 606th. On Gemini, they were nearly neighbours: 29th and 60th.

Who actually carries your brand?

The old SEO instinct says start with your website. AI visibility makes that less reliable, and the numbers are blunt about it. In the U.S., Chevrolet, Disney, Ford, Honda, Marvel, Nintendo, and Toyota all ranked top 100 for mentions across all four platforms — and all sat outside the top 500 for citations, every single month measured.

That puts some AI visibility work outside SEO's remit. When the brand appears but its site doesn't, inspect the pages that do get cited: publishers, retailers, community sites, reference platforms. The fix might belong with content, engineering, or communications rather than SEO.

"Create more content" is a weak default when the source gap lies elsewhere.

Does category matter as much as platform?

More, actually. Semrush found that differences between categories exceeded differences between platforms on mention-to-citation overlap in every month measured. Even within the U.S., broad benchmarks can mislead.

U.S. Real Estate had the same source domains appear across all four platforms every month: Apartments.com, Realtor.com, Redfin, and Zillow. U.S. Industrial had no equivalent recurring source core. A real estate team gets a stable set of sources to work with; an industrial team needs specific competitor and customer questions before a broad-category benchmark says anything useful.

So a useful AI visibility question needs four things attached: the customer question, the competitor set, the platform, and the category. Start with separate mention and citation baselines for a fixed set of customer questions, then inspect the answers and cited pages before funding a tactic.

One caution worth keeping. Semrush's study doesn't establish that a change in AI visibility caused any commercial result, so keep business outcomes separate from visibility measures.

Diagnose the type of gap first. Then hand the work to the team that can actually fix it.

The full report can be downloaded at ai-visibility-index.semrush.com. Registration required.

By Sophie Lindqvist