GEO vs AEO vs LLM SEO: One Service, Four Names (and Why the Label Changes Which Agencies You Find)

That is odd, because LLM SEO, GEO and AEO are three names for the same job: getting ChatGPT, Gemini, Perplexity and Google’s AI Overviews to mention and cite your business. AI SEO is the fourth name, and the plainest.

If the acronyms have left you unsure whether you are comparing four services or one, that is not your fault. The vocabulary is a mess, and every page-one result we read on 22 October was written by a firm selling a tracker or the service itself.

I’m Devon Kellar and I run GEO Agency Directory, where I’ve hand-checked 246 agencies’ service pages. Below is what each name means, what those agencies actually call the work, and why the label you type into Google decides which slice of the market you get to see.

What is LLM SEO, and why do so few agencies sell it under that name?

LLM SEO, also written LLMO, is optimising a business so that large language models such as ChatGPT and Gemini mention it, cite it and describe it accurately. Buyers search for it: Ahrefs puts “llm seo” at 500 UK searches a month. Sellers barely use it. Of the 246 agencies in GEO Agency Directory, checked on 22 October 2026, only 12 use the label on their own service page (9 say LLMO, 3 say LLM SEO).

The term has no agreed origin. There is no paper behind it and nobody credibly claims to have coined it. It shows up mostly in tool vendors’ glossaries, often alongside “LLM optimization”, and it has spread because it describes the target plainly: the model, not the search engine.

So buyers search for the one phrase that sellers barely use. Google still fills the page when you search “llm seo agency”, but it fills it from a different pool: tool vendors, glossaries and the few firms that optimised for that exact phrase. The agencies that file the same work under GEO or AI SEO mostly don’t appear. Plenty of firms do this work. Most just call it something else, and the overlap data further down shows what that costs a searcher.

LLM SEO, GEO and AEO: where each name came from

GEO is the only one of the four names with a primary source. It comes from the paper “GEO: Generative Engine Optimization” by Pranjal Aggarwal and colleagues, first posted to arXiv in November 2023 and accepted to KDD 2024. AEO is an older snippet-and-voice-era term stretched to cover AI answers. LLM SEO has no paper, and AI SEO is simply the plain-English label. GEO is also the most common label in practice, used on 154 of the 246 agency service pages we have verified.

The GEO paper is worth reading in full at arXiv:2311.09735. Its authors introduced a benchmark called GEO-bench and report that “GEO can boost visibility by up to 40% in generative engine responses.” They also found the effect varies across domains. In practice, that means what works for a law firm may not work for a software company.

AEO borrowed its goal from the featured snippet era: be the single answer a machine reads out.

To me, the acronyms differ in history and in nothing else that matters to a buyer. Nobody arrives at your office with a different toolkit because their homepage says AEO instead of GEO.

Are GEO and AEO actually different services?

No, not in practice. Of the 246 agencies GEO Agency Directory has hand-verified against a published service page, 105 (43%) sell under two or more of the five core labels (GEO, AI SEO, AEO, LLMO and LLM SEO), and 28 sell under three or more. If the labels named separate services, that overlap would not exist on the agencies’ own pages.

The counting rule is strict: a label counts only if the agency’s own service page uses it. The full inclusion test is on our methodology page.

Why five labels when the title says four names? We count LLMO and LLM SEO separately because agencies tag them separately, but they are one name spelled two ways.

GEO is the most common of the five (154 agencies), but AI SEO (120) and AEO (90) are both large, and many firms use all three. Contently’s explainer calls GEO the label everything is converging on. Our counts don’t support that. They show three big labels used side by side, often by the same firm.

So what is the real difference in the geo vs aeo argument? Emphasis. AEO leans towards getting your content extracted as the direct answer to a question. GEO leans towards getting your brand cited inside an answer the engine assembles from several sources. Both are achieved with the same pages, the same entity work and the same third-party mentions.

The deliverables are the same, and only the emphasis shifts. When an agency claims its AEO is a different product from someone else’s GEO, ask to see the work plan. You will usually find the same line items.

GEO vs SEO: what changes and what doesn’t

SEO aims to win a ranked link and a click. GEO aims to win a mention or citation inside the answer itself. The foundations are shared: crawlable pages, clear headings, well-defined entities and mentions on third-party sites. The GEO paper by Aggarwal and colleagues (arXiv, November 2023) built its own benchmark to measure visibility in generative engine responses and reports gains of “up to 40%” there, a different scoreboard from a ranking position.

That shared base matters when you brief anyone. You do not need to throw out your SEO to start on GEO. If your pages can’t be crawled or don’t say clearly who you are and what you do, no AI engine will cite them either.

Use this as a filter in agency interviews. An agency selling GEO with no interest in those foundations is selling one of two things: a renamed SEO retainer or a monitoring dashboard. Neither is necessarily bad, but you should know which one you are buying.

How much traffic is at stake? Nobody agrees. Published estimates of AI referral traffic vary widely depending on whose tracker produced them, and most of those trackers are sold by firms with something to gain. If an agency opens its pitch with one confident figure for how much traffic AI will send you, ask where it came from. You will usually find a vendor’s blog, not a study.

One last trap. In older SEO writing, “geo” also means geographic targeting. When we spot-checked the UK top 10 for “geo agency”, every result used the generative sense, but check which meaning a page intends before you trust its advice.

Why the name you search changes the agencies you find

On UK Google, the top 20 results for “geo agency”, “aeo agency”, “ai seo agency” and “llm seo agency” share at most four domains between any two searches, and no domain appears in all four. That comes from GEO Agency Directory’s fixed Serper panel (Google UK, top 20, run on 23 September 2026). Each search returned 18 or 19 domains.

Read the matrix as a buyer would. Someone who searches “geo agency” and someone who searches “ai seo agency” share exactly one domain across two lists of 18. They are shopping for the same work and seeing almost entirely different results.

The best pairing, geo and aeo, still shares only four domains. Even then, most of each list is invisible to the other searcher.

A single-label search doesn’t give you a smaller sample of the market. It gives you a different market, chosen by which acronym happened to come to mind. Combine that with the 105 agencies that sell under two or more labels and the picture is clear: the agencies overlap heavily, while the search results barely overlap at all.

This is one run, on UK Google only, with “agency” added to each query. It says nothing about the US, Singapore or what AI engines themselves recommend. We measure Google visibility, not AI citations.

The practical fix is to search more than one label, or to start from a list that already spans them. That is why this directory keeps three rankings: the best GEO agencies, the AI SEO agencies ranked by visibility and the best AEO agencies. Each list uses the same ranking method, so you can compare across them like for like.

Which term should you use when hiring an LLM SEO agency?

Use whichever term your boss or board understands. In our experience that is usually AI SEO, the plainest of the four. The label tells you nothing about quality: in GEO Agency Directory’s count of 246 verified agencies, 105 sell under two or more names for the same work. So search at least two labels before you build a shortlist.

Then ignore the acronym and vet the work. Three questions do most of the job:

• What will you actually change on our site and off it, month by month?
• Which AI engines do you track, and with what prompts?
• How do you report citations, and can we log in to the tracker ourselves?

Never ask which acronym they prefer. You will get a sales pitch, not information.

Be ready for a wide range behind the same label. A “GEO service” can be anything from a monitoring dashboard to an SEO retainer with a new name on the invoice. The test we use for inclusion is simple and you can copy it: does the firm publish a service page that describes the work? Our methodology explains how we apply it.

If you want a starting point that already spans the vocabulary, begin with AI SEO agencies ranked by visibility, then cross-check the GEO and AEO lists. If you would rather skip the vetting, you can request proposals from several verified agencies and compare their work plans side by side.

Search at least two labels, then judge every agency on its work plan.

How we counted: counts come from GEO Agency Directory’s master list (246 agencies, 22 October 2026). A label counts only if the agency’s own service page uses it, and only the five core labels count; tallying any service tag such as SEO or PPC would qualify 245 of 246 agencies and mean nothing. Overlap figures: Google UK top 20 via Serper (gl=uk), 23 September 2026, for “geo agency”, “aeo agency”, “ai seo agency” and “llm seo agency”. UK and Google only. Full method: methodology.