GEO vs AEO vs AIO vs LLMO: Are They Different, and What Should You Buy?

Picture a dental practice in Warrington. On Monday an agency emails offering “GEO”. A week later a second agency pitches “AEO”. Then a third sends a bundle called “AIO and LLM SEO”.

Three proposals, three acronyms, and each one sounds like a new specialism you can’t afford to miss. Are they three services, or one service priced three ways?

That is the real question behind GEO vs AEO, and Google has an unexpectedly blunt view on it, quoted below. The short version: these labels mostly describe one job, with one genuine distinction inside it.

This guide covers what each acronym means, where it came from, the one difference that matters, and what to check before you sign. If you want the GEO basics first, start with our plain-English guide to GEO.

GEO vs AEO vs AIO vs LLMO vs SEO: The Short Answer

Google uses these terms itself. Its guide to optimising for generative AI features (updated 10 July 2026) calls AEO and GEO “terms you may see used to describe work specifically focused on improving visibility in AI search experiences”, then adds that this work is “still SEO.” That covers Google’s own AI features, not ChatGPT.

The direct answer: GEO, AEO, AIO, LLMO, LLM SEO and AI SEO are mostly different names for the same work, getting your business named and cited in AI-generated answers. Where people draw a line, AEO means structuring answers on your own pages so a machine can lift them, and GEO is the wider umbrella that also covers your reputation on sites you don’t own.

Where they all differ from plain SEO is citation versus ranking. An Ahrefs study of 863,000 keyword results (March 2026) found 37.9% of URLs cited in Google’s AI Overviews also rank in the top 10, while 31% sit beyond the top 100. Ranking helps, but citation is a related job. See our guide to appearing in Google AI Overviews.

1. AEO (Answer Engine Optimisation): The Oldest Label, With Four Definitions

AEO was being pitched years before anyone had heard of ChatGPT. So what is it doing in a 2026 AI proposal?

It grew out of optimising for Google’s featured snippets, knowledge panels and voice assistants, with sources dating the term to roughly 2014 to 2018 (Profound). When AI answers arrived, the label was re-purposed. Ahrefs now uses AEO as its main term, Semrush reportedly does too, and Ahrefs’ AEO course says GEO and LLMO “all mean essentially the same thing.”

The catch is that AEO means different things depending on who is selling it:

• SERP features: featured snippets, People Also Ask and Places results (Progress).
• Voice search: full-sentence spoken questions, in some local marketing providers’ definitions.
• Google’s AI Overview box: getting your words pulled into that summary, in others.
• Any AI answer: ChatGPT, Gemini, Perplexity and the rest (Ahrefs).

Same three letters, four scopes. That is the first thing to ask about in any geo vs aeo pitch.

What AEO work looks like on a local site is refreshingly concrete. A question as the heading (“How much does a boiler service cost in St Helens?”), the answer in the first two sentences, and a genuine FAQ block written in the words customers actually use. This matches how we describe AEO in our GEO guide.

One honest caveat. Progress warns that FAQs shoehorned onto pages where they don’t belong make the page worse for the people reading it. Google’s own guide is also clear: “You don’t need to write in a specific way just for generative AI search.”

Best for: tidying service and area pages so the answers are easy to lift. Skip if: it’s sold as a separate retainer from your SEO. This is on-page work any competent SEO already does.

2. GEO (Generative Engine Optimisation): The Umbrella Term, and the Local Business Name Clash

GEO started in a university paper, not at an agency. “GEO: Generative Engine Optimization” by Pranjal Aggarwal and colleagues was first submitted in November 2023 and presented at the KDD 2024 conference. Its headline finding was that GEO methods could boost visibility “by up to 40%” in generative engine responses, with results varying by subject. That is a ceiling from lab tests, not a promise for your practice. Investment firm a16z then made GEO the investor and vendor default with a May 2025 essay.

For a local business, the name has a problem. “Geo” already means geography: geo-targeted ads, geo pages, “local geo SEO”. Profound calls GEO “not ownable” for exactly this reason. If a proposal says GEO, check whether it means AI answers or location pages, because those are different jobs.

What GEO adds over AEO is the one real distinction in this whole geo vs aeo debate: your reputation beyond your own website. As Ahrefs puts it in its AEO video, “a lot of AEO isn’t about what’s on your site, it’s about getting mentioned on other people’s pages.”

For a Liverpool solicitor or a Widnes roofer, those other pages look like reviews, directory listings, local press and trade body pages. None of that lives on your website, so on-page tidying alone can’t cover it.

The mentions have to be real, though. Google’s same guide warns that “seeking inauthentic ‘mentions’ across the web isn’t as helpful as it might seem.” A GEO proposal promising a fixed number of placements every month deserves a hard look at where they come from.

We won’t re-explain how GEO works here. For that, and a free way to check your own visibility, see our guide to GEO. For the ChatGPT side specifically, read how to get mentioned in ChatGPT.

Quick comparison: AEO tidies the answer on your page. GEO also asks whether the rest of the web vouches for you. Most sensible providers sell them as one service.

3. AIO: Why This Acronym Means Three Different Things

Imagine a monthly report with a line that simply says “AIO up”. Up in what? (A made-up example, but a realistic one.) It could mean you appeared in more Google summaries, that more pages were written with AI, or nothing measurable at all.

AIO is the most ambiguous label on this list. In current writing it carries at least three meanings, according to one AI search glossary and other industry write-ups:

1. Google AI Overviews. The AI summary at the top of Google results. This is the most common use in SEO writing.
2. “AI optimisation”. Some providers use it for a whole-footprint trust layer: reviews, listings and consistent business details across the web. In practice, that is GEO under another name.
3. Using AI tools to write or speed up SEO content. Nothing to do with being recommended by AI at all.

Meaning two is where buyers get caught. If a proposal lists AIO and GEO as separate line items and both describe reviews, listings and mentions, you are being asked to pay twice for one job. Ask the provider to show you a deliverable under one heading that does not appear under the other.

Direct recommendation: if AIO appears on a proposal, ask which of the three meanings it is and which deliverable it pays for. If the answer is the third, you are buying content production, not AI visibility.

4. LLMO, LLM SEO and AI SEO: Same Job, Named After the Technology

If LLM SEO were a separate discipline, you would expect its own tactics. Line its tactics up against GEO’s and the two lists are identical.

Start with the definitions:

• LLMO: Ahrefs says “LLM optimization (LLMO) is all about proactively improving your brand visibility in LLM-generated responses” and adds, “Think of LLMO as a new kind of SEO.”
• LLM SEO: the same thing with “SEO” bolted on. An LLM, or large language model, is the technology behind the answers in ChatGPT, Gemini, Claude and Perplexity.
• AI SEO: Wikipedia lists it among the alternative names for GEO, alongside AEO, LLMO and AIO, and notes there is no consensus definition.

Google’s Danny Sullivan made the same point at WordCamp US in August 2025, as reported by Search Engine Land: “Good SEO is good GEO, or AEO, AIO, LLM SEO, or LMNOPO.” He works for Google, so weigh that accordingly.

The label doesn’t change the method because the plumbing is shared. ChatGPT uses Bing’s index when it searches the web, as one SEO course from Surfer points out. So the same basics apply: a crawlable site, clear facts about your business, and a reputation elsewhere. Our ChatGPT guide covers those rather than us re-listing them here.

The one trap is “AI SEO”. Some agencies use it to mean AI-written content at volume. Ask whether a person edits every page, and whether the work is about being recommended by AI or about producing pages faster.

Even the tool vendors split on labels. One comparison reports Ahrefs has leaned on LLMO and now AEO, Semrush on AEO and Surfer on GEO. Label choice is branding.

The verdict: an “LLM SEO specialist” and a “GEO agency” should be selling the same deliverables. Judge them on those.

What to Actually Buy: Ignore the Acronym, Check the Deliverables

One question cuts through every acronym on this page: “What will you actually do each month, and how will I see it?”

To recap. SEO is the foundation: Google says there are “no additional requirements to appear in AI Overviews or AI Mode” beyond being indexed and eligible for a snippet. AEO and GEO are mostly the same work under different names. The genuine extras are tracking what AI tools say about you, and building real mentions elsewhere.

Whatever the proposal calls it, it should name:

1. The customer questions being tracked, and in which AI tools.
2. The on-page changes to your service and area pages.
3. Where real mentions and reviews will come from.
4. How it fits with your existing SEO, so you aren’t paying twice.

For what this should cost, which items can fairly cost extra and the red flags to look for, see our guide to GEO costs in the UK.

Be wary of urgency. Google’s John Mueller put it plainly on Bluesky: “The higher the urgency, and the stronger the push of new acronyms, the more likely they’re just making spam and scamming.” One founder who reviewed ten GEO and AEO agencies for a software business reached a similar verdict: “Eight of them are running 2019 SEO playbooks with new vocabulary.” To be fair, using the word GEO doesn’t make anyone a cowboy. The warning sign is urgency plus vagueness.

We run SEO and GEO as one service. For one anonymised vet clinic in Manchester, Google AI Overview appearances went from 6 to 165 year on year (August 2025 to August 2026, tracked in Semrush), and it is the practice ChatGPT recommends first when asked for one in its area. The details are on our case studies page. No one can honestly guarantee rankings or AI mentions, and we don’t.

See what our GEO service includes, then request a quote or call us for a straight answer on whether it’s worth it for your business.

FAQ

Is AEO part of GEO?

Usually, yes. Where a line is drawn, AEO is the answer-formatting part of the wider GEO umbrella: question headings, direct answers and genuine FAQs that a machine can lift. GEO also covers reviews, mentions and listings on sites you don’t own. In everyday use the two terms are swapped freely. See the AEO section above for the four definitions in circulation.

What is LLM SEO?

LLM SEO means optimising so that large language models such as ChatGPT, Gemini and Claude mention and cite your business. It is the same job as GEO and LLMO, just named after the technology. Ahrefs describes LLMO as “proactively improving your brand visibility in LLM-generated responses”. If a specialist sells it as something separate, ask which deliverables differ.

Is AI SEO the same as GEO?

In most usage, yes. Wikipedia lists AI SEO as an alternative name for GEO, alongside AEO, LLMO and AIO. The exception is when someone uses “AI SEO” to mean using AI tools to write SEO content, which is a different service entirely. If it’s on a proposal, ask which one is meant before you sign.

Is GEO replacing SEO?

No. Google’s July 2026 guide says optimising for its generative AI search “is optimizing for the search experience, and thus still SEO”, and AI Overviews only use pages that are indexed and eligible for a snippet. Ranking and AI citation overlap without being identical: Ahrefs found 37.9% of AI Overview citations come from top-10 results. GEO builds on SEO.

What does AIO mean in SEO?

Most often, AIO means Google AI Overviews, the AI summary at the top of some search results. Some providers use it for “AI optimisation”, which is effectively GEO under another name, and others for using AI tools to produce content. Because the meanings differ so much, always ask which one a proposal means. See the AIO section above.