SEO vs AEO vs GEO: What's the Difference?

If you run a small business in the UK, the odds are good that someone has tried to sell you at least one of these acronyms this year. The pitch changes depending on which letters they favour. The invoice, oddly, does not. And the interest is not misplaced: over half of UK adults (54%) now use AI tools such as ChatGPT, up from 31% in 2024 (Ofcom Online Nation, 2025). That is a genuine shift in how people find things, and it is worth understanding before you spend money on it.

So let me define each term the way I would explain it to a client over coffee, show you where they actually differ, and hand you the exact questions to ask before you pay anyone a penny.

What is SEO?

Search engine optimisation (SEO) is the practice of improving a website so it ranks higher in traditional search results, which for most people still means Google's list of blue links. The work spans technical health, relevant content and credible backlinks, but the goal underneath it is dead simple. When someone searches for what you sell, your site needs to sit high enough on the page to earn the click.

SEO has been around for roughly three decades now, and the honest truth is that the fundamentals have barely moved. A site search engines can crawl. Pages that load quickly. Content that answers what people are genuinely typing in. Mentions from sites worth trusting. None of that has aged, and it is not going to. It also does something people forget: it feeds everything I am about to describe, because the AI systems learn about your business from the very same web that Google indexes.

What is AEO?

Answer engine optimisation (AEO) is about becoming the answer an AI assistant or answer box actually gives, instead of one link among a hundred. The targets here are tools like ChatGPT, Copilot, Gemini and Google's AI Overviews. You win when your business gets named, quoted or recommended the moment a customer asks a question, because in that format there is no page two to climb to.

The phrase started life around featured snippets and voice search, but these days it is mostly shorthand for the AI assistants. That matters because the surface is already in front of your customers: more than half of UK adults (53%) say they often see AI-generated summaries at the top of their search results (Ofcom Online Nation, 2025). Winning that space comes down to a few things done well, namely content built as direct answers to the questions real customers ask, business information that stays consistent everywhere it appears, and a presence in the sources the assistants lean on. I go deeper on the practical side in our guide to getting recommended by ChatGPT.

What is GEO?

Generative engine optimisation (GEO) is the practice of influencing what generative AI engines write about a topic and which sources they choose to cite. The label traces back to a 2024 research paper out of Princeton and IIT Delhi (Aggarwal et al., 2024). In the field, it overlaps so heavily with AEO that the two names get used interchangeably more often than not.

The research is worth actually knowing, because it gets waved at business owners constantly and rarely with the caveats attached. The team tested nine content adjustments across a benchmark of 10,000 queries and measured how visible each source became in the AI-generated answers. The winners were adding quotations, adding statistics and citing credible sources, which lifted visibility by up to 40% on the paper's metrics. Keyword stuffing, that hoary old search tactic, flopped. Here is the part the sales decks tend to lose along the way: the results varied significantly from one domain to the next, and the whole thing ran in a controlled research setting. It was never a promise about how your particular business will fare (Aggarwal et al., 2024).

SEO vs AEO vs GEO at a glance

All three lean on the same groundwork; where they part ways is in where the result shows up and how you know it worked. SEO earns you rankings and clicks on a results page. AEO earns you a spot inside the single answer an assistant hands back. GEO shapes what the generative engines write and who they credit for it. Here is the whole thing side by side.

What is actually different, and what is marketing spin

Strip away the branding and most of what sits behind these three acronyms is identical: a healthy site, clear content, and credible mentions on other people's sites. The differences that hold up are narrow. There are really only three, and anything sold to you as a separate secret discipline beyond them is repackaging.

The three that are real:

• Answer-shaped content. AI engines pull things apart and stitch them back together. Content that raises a clear question and answers it straight away, in a paragraph that stands on its own, gets picked up far more often than a page written purely to rank.
• Citations in the sources AI reads. The assistants lean on directories, review platforms, trade publications and reference sites. Getting mentioned in those places carries weight it simply did not have back when rankings were the only currency.
• Machine readability. Clean structure, structured data and facts about your business that agree with each other make it far easier for a model to lift the right information and repeat it accurately.

The rest of the usual pitch, from technical fixes to content plans to chasing reviews, is ordinary SEO with a fresh badge sewn on. I am not saying it is useless. I am saying it is familiar, and familiar work should be priced like familiar work.

Which one should a small business buy?

For most small businesses the answer is straightforward: keep your SEO fundamentals in good shape and add the AI visibility work on top of them. It is one discipline pointed at a bigger target, not three services to line up in a row. Buy GEO as a standalone package and you are usually just paying a second time for overlapping work under a shinier label.

Here is how it plays out in practice. If your website has basic problems, slow pages, thin content, opening hours that say three different things in three different places, fix those before anything else, because every AI system is reading the same broken site your customers are. With the foundations solid, then you layer on the AI-specific work: answer-shaped pages, structured data, citations in the sources the assistants actually pull from, and a monthly check on what the AI is really saying about you.

The one thing I would steer you away from is buying SEO from one supplier and GEO from another. The tactics overlap so much that you would be paying two agencies to edit the same handful of pages. Our UK guide to AI search optimisation walks through running the whole thing as a single programme.

Questions to ask any agency selling you GEO

Before you sign anything, put four questions to them. Can they show evidence their work actually moved AI visibility for a real client? Do they guarantee outcomes? What will they measure and report to you every month? And who does the implementation? The answers sort the practitioners from the people reselling a trend, quickly.

• Can they show evidence? Ask for a proper before-and-after: what the AI assistants said about a client at the start, what got changed, and what those same assistants said three months on. You want the exact answers and the dates, not a page of adjectives.
• Do they guarantee outcomes? If the answer is yes, walk. Nobody controls what an AI assistant says, and the answers shift with phrasing, with the user, with the day of the week. Honest suppliers talk to you about baselines and movement, never promises.
• What do they measure monthly? What you are after is a repeatable test: the same set of buyer questions, put to the same assistants each month, with your share of the mentions tracked over time. If the answer is woolly, the reporting will be woolly too.
• Who does the implementation? Recommendations with nobody to act on them are just homework. Ask flat out whether they change the pages, publish the content and fix the data themselves, or whether you get a PDF and a retainer invoice.

Questions people ask

These are the ones UK business owners bring to us most often about SEO, AEO and GEO. Each answer stands on its own, so read whichever applies. And if yours is not here, the honest one-line version is this: the labels matter far less than the work, and the work overlaps heavily across all three.

Is AEO the same as GEO?

In practice, mostly yes. Both aim to get your business named and cited in AI-generated answers. AEO tends to emphasise being the single answer to a question, while GEO comes from academic research on influencing what generative engines write. Most agencies use the terms interchangeably, and the underlying work is largely the same.

Do I still need SEO if AI search is growing?

Yes. AI assistants learn about your business largely from the same sources search engines index, so a crawlable site, clear content and credible mentions still matter. Traditional search still drives most discovery for most UK businesses. Treat AI visibility as an extension of your SEO work, not a replacement for it.

How long does AI visibility work take?

Typically weeks to a few months before you see movement, depending on how often each AI system refreshes its sources. Changes to your own site can be picked up quickly by assistants that browse the web, while shifts in third-party sources take longer. No specific timescale can be promised.

Can an agency guarantee my business will appear in ChatGPT?

No, and you should treat any guarantee as a warning sign. AI assistants generate answers probabilistically, and results vary by phrasing, user and day. A credible agency will show baseline measurements, make targeted changes and report movement monthly, but it cannot control what any assistant says.

Sources

Every statistic in this article is attributed inline to one of the sources below, and we link straight to the primary material so you can check each claim for yourself. Where a number carries no attribution, treat it as our professional judgement rather than a measured fact.

• Ofcom, Online Nation 2025 report
• Aggarwal, P. et al., GEO: Generative Engine Optimization, ACM KDD 2024 (arXiv)