What Is Generative Engine Optimisation (GEO)? A Plain-English Guide for UK Businesses

Generative engine optimisation is the practice of shaping your website and wider online presence so that AI answer tools find your content, trust it and use it in their responses. Researchers call these tools generative engines: ChatGPT with search, Google's AI Overviews and AI Mode, Gemini, Perplexity and Microsoft Copilot. Each reads a set of web pages, then writes one answer that summarises them, usually with links to its sources.

The name comes from a research paper titled GEO: Generative Engine Optimization, first published in November 2023 by researchers from Princeton University and partner institutions, and accepted to the KDD 2024 conference. They built a large benchmark of search queries and tested which content changes made a source more visible in AI answers. Their headline finding was that the right changes could boost visibility by up to 40%, and that what works varies from one subject area to another.

In practical terms, GEO asks three questions of your business. Can the AI tools read your pages? When they read them, is there a clear, quotable answer to the question being asked? And does the rest of the web agree with what your site says about you?

There is far more overlap than the new acronym suggests. Google's own guidance on AI features and your website says the same foundational SEO best practices apply to AI Overviews and AI Mode, and that there are no additional technical requirements beyond being indexed and eligible to show with a snippet. If your SEO is weak, your GEO will be weak too.

The differences are in what you are competing for and how it is judged.

• The unit is the answer. Classic search ranks whole pages in a list. A generative engine lifts a passage, a fact or a definition and blends it with others, so a page wins by containing the clearest answer to one specific question.
• Mentions count beyond your own site. When an assistant recommends a business, it draws on what reviews, directories, press and other sites say, as well as your own pages.
• The click is worth more. Google says that when people click through from results pages with AI Overviews, those clicks are higher quality, with visitors more likely to spend longer on the site.
• Old tricks backfire. In the GEO research, keyword stuffing performed worse than leaving the content alone, while adding citations, quotations from relevant sources and statistics improved visibility.

We treat SEO, AEO and GEO as one piece of work with three outputs, which is why our SEO, AEO and GEO service runs as a single engagement. AEO, answer engine optimisation, is the close cousin focused on being quoted as the direct answer to a question.

None of the companies publishes its full method, so be wary of anyone claiming the exact formula. What is documented is enough to act on.

Google AI Overviews and AI Mode

Google draws on its normal search index. To appear as a supporting link, a page has to be indexed and eligible for a snippet. Google also describes a "query fan-out" technique, where the system runs several related searches across subtopics to build one answer. So a question such as "best way to treat damp in a Victorian terrace" can pull in pages answering several narrower questions, which gives a specific, well-structured page more chances to be picked.

ChatGPT search

OpenAI uses a crawler called OAI-SearchBot to surface websites in ChatGPT's search features. Its crawler documentation is blunt: sites that block OAI-SearchBot will not be shown in ChatGPT search answers. A separate crawler, GPTBot, collects content that may be used for model training, and you can block one while allowing the other.

Gemini, Perplexity and Copilot

These work on the same broad principle: retrieve pages from a search index, read them, then write an answer with citations. The practical upshot is consistent across all of them. They favour pages they can crawl, text that answers the question directly, facts that match what other sources say, and content that shows its evidence.

Yes, and it adds to Google search, which remains the bigger channel. Ofcom's Online Nation 2025 report found that about 30% of UK searches now show an AI Overview and 53% of adults say they see these summaries often. ChatGPT had 1.8 billion UK visits in the first eight months of 2025, up from 368 million in the same period of 2024. Google launched AI Mode in the UK in July 2025.

The same Ofcom report found Google Search is used by 82% of UK adults, with 3 billion searches a month. Classic search is still where most enquiries start. Our work for Pest & Property Solutions, a Cardiff pest control company, shows it: 82.7% of the enquiries from its new site came from Google organic search. GEO is the layer you add so that you are also present when the same customer asks an AI tool.

For a Cardiff business the stakes are local. Someone asking an assistant for "a reliable electrician who covers Whitchurch and Llandaff" gets a short list of names. If your website, Google Business Profile and reviews clearly say which areas you cover, the assistant has something solid to work with. If your service areas are buried in an image, you leave the shortlist to whoever wrote theirs down.

None of this needs a new website. Work through it in order, because the first steps are the ones most often broken.

1. Check the doors are open. Look at your robots.txt file and make sure it does not block Googlebot, Bingbot or OAI-SearchBot. Google also asks you to check your CDN or hosting, as some security settings block crawlers quietly.
2. Answer the question at the top of the page. For each important service page, write a 40 to 60 word answer to the main question a customer asks, in plain text near the top. "We repair and replace flat roofs across Cardiff and the Vale of Glamorgan, with a written quote after a free survey" is quotable. "Excellence in every project" gives a model nothing to use.
3. Put your facts in text. Prices or price ranges, areas covered, opening hours, accreditations you actually hold. If it only exists in a PDF or an image, assume the AI tools will miss it. Add structured data that matches the visible text, as Google asks.
4. Make the web agree with you. Your business name, address, phone number, services and areas should match across your site, Google Business Profile and the main directories. Google lists an up-to-date Business Profile among its recommendations for AI features, and conflicting details give an assistant a reason to pick someone else.
5. Show your evidence. The GEO research found that citing sources, adding quotations from relevant sources and including statistics improved visibility. For a small business, that means linking to the regulation or standard you follow, naming the person who wrote the advice, and publishing real figures you can stand behind.
6. Write the FAQs people actually ask. Take the questions you hear on the phone every week and answer each one in a short, self-contained paragraph. These map closely to the narrower searches that query fan-out runs.
7. Earn mentions elsewhere. Reviews that describe the job, a trade association listing and a quote in local press all give assistants more to draw on.

If you want a quick view of where you stand before you start, our free Cited AI visibility check scores 15 signals that affect whether AI tools can find and recommend you.

Measurement is still immature, but it improved a great deal this year.

• Search Console. Google introduced generative AI performance reports in Search Console in June 2026. They show how often your URLs appear in AI Overviews, AI Mode and AI features in Discover, broken down by page, country, device and date. Google completed the worldwide rollout on 31 August 2026. The reports show impressions only, with no click data yet, and sites with few AI impressions may not see one.
• Analytics referrals. In GA4, look at referral traffic from chatgpt.com, perplexity.ai, gemini.google.com and copilot.microsoft.com. Volumes are often small, so watch enquiry form completions more than sessions.
• A fixed prompt test. Write ten questions a real customer would ask, such as "who installs commercial EV chargers in Cardiff?", and run them in ChatGPT, Gemini and Google AI Mode on the first working day of each month. Record whether you are mentioned and which page is linked. Answers vary between runs, so look for the trend over three months.

Tie all of it back to enquiries. Visibility that never turns into a phone call or a form is a vanity number.

GEO is worth doing, with caveats a good adviser will tell you upfront.

• Nobody controls the answer. The models change, answers vary from one run to the next, and the original researchers described generative engines as black boxes. Anyone guaranteeing you first place in ChatGPT is guessing.
• Results vary by sector. The research found the effectiveness of each method differed across domains, so what works for a solicitor may do little for a café.
• Clicks are uncertain. Being cited does not always produce a visit, and Search Console does not yet report AI clicks. Judge GEO on enquiries over months.
• The rules are moving. In June 2026 the UK's Competition and Markets Authority required Google to let websites opt out of its AI search features without being penalised in standard results, and Google added that control to Search Console. The CMA has given Google until March 2027 to offer page-level controls. Expect more change.

None of this is a reason to wait. The groundwork for GEO is the same groundwork that makes a website convert: clear answers, accurate facts and proof.

GEO works best when it is built into how your website and content are run each month. At Roddy Digital, an AI-first agency in Cardiff, we fold it into the same programme as SEO and content: technical access first, then answer-first pages, consistent business data and monthly measurement against enquiries. Our generative engine optimisation service sets out how it works.

For wider context, read our free report Your Next Customer Won't Google You, or our guide on how to get found on Google for the search foundations GEO builds on.