What Is GEO? Generative Engine Optimisation — The 2026 Guide for UK Agencies

Search is no longer just a list of links. Buyers now ask ChatGPT, Perplexity, Gemini and Google’s AI Overviews for vendor shortlists, comparisons and recommendations — and they trust the answer the machine gives them. For UK agencies, that means a new visibility problem: it’s not enough for your clients to rank. They need to be named, quoted and recommended inside the AI’s answer itself.

GEO is the discipline of earning that place. It covers everything that makes generative AI systems cite your brand as a trusted source: clear entity definition, quotable content, independent mentions across the web, and visibility measured across engines. Want to see where your agency — or your clients — stand in AI answers? Book a free consultation with Spurtech and we’ll walk you through an AI-visibility baseline.

What is GEO? The direct answer

GEO (Generative Engine Optimisation) is the practice of optimising a brand’s content, entity signals and online reputation so that generative AI engines — ChatGPT, Perplexity, Gemini, Google AI Overviews and Copilot — cite, quote or recommend that brand inside their synthesised answers. Where SEO wins positions in a list of links, GEO wins inclusion in the answer the engine writes.

The concept has an academic origin. In November 2023, researchers from Princeton University, Georgia Tech, the Allen Institute for AI and IIT Delhi published the paper GEO: Generative Engine Optimization (arXiv:2311.09735), the first creator-centric framework for measuring and improving content visibility inside generative engine responses. Their benchmark, GEO-bench, tested content tactics across roughly 10,000 queries and found that targeted optimisations could lift a source’s visibility in generated answers by up to 40%. The effective tactics were not what most marketers expected: keyword stuffing did little, while adding citations, expert quotations and statistics moved the needle.

How did the Princeton GEO research define the problem?

The paper’s framing is worth keeping, because it explains why GEO is not “SEO with a new name”. Traditional search returns a ranked list of documents and the user does the synthesis; generative engines do the synthesis themselves — retrieving sources, reading them and composing a single answer. The creator’s problem changes from “how do I rank?” to “how do I get picked as a source?” Three findings shaped every serious GEO playbook since:

• Visibility means citation, not ranking. The paper introduced metrics around how often — and how prominently — a source appears in generated responses, rewarding sources cited early and at length.
• Credibility signals beat optimisation signals. The most reliable tactics were adding citations to credible sources, adding direct quotations, and adding statistics with clear attribution.
• Tactics vary by domain. Effectiveness differed across topics, so GEO needs domain-specific tuning rather than a one-size-fits-all checklist.

If you’d like the industry-side companion to the academic paper, Go Fish Digital’s comparison of GEO agencies versus SEO agencies translates the research into agency workflows — including the paper’s headline figures, such as quotation addition improving a position-adjusted visibility measure by around 41% and statistics addition lifting subjective impression scores by around 28%.

How do generative engines choose what to cite?

Different tools work differently, but a typical generative answer goes through four stages:

1. Interpretation. The engine breaks the user’s question into what it needs to know. Long, conversational queries get decomposed into sub-questions and related angles.
2. Retrieval. It gathers candidate sources from live indexes or training data. If your page can’t be crawled, read and understood quickly, you’re out before the answer is composed.
3. Reading and judgement. It reads the candidates and judges which answer the question clearly, with evidence. Sourced claims, clean structure and consistent entity information win here.
4. Composition with citations. It writes one answer and cites the sources it leaned on. Most AI answers cite a small handful of sources — typically two to seven domains — which is why competition for each answer is intense.

The second stage is where most brands lose. Perplexity leans heavily on real-time retrieval and community discussions; ChatGPT weighs consensus sources such as Wikipedia; Google’s AI Overviews overlap substantially with traditional organic rankings — so a page that ranks well in Google is far more likely to be cited by an AI Overview. As Technology.org’s 2026 GEO guide puts it, GEO is therefore not a single optimisation target but a portfolio of them: one piece of content can perform very differently across engines.

What is the difference between GEO, SEO and AEO?

The three disciplines share foundations but optimise for different outputs. If you read our companion guide on what AEO (Answer Engine Optimisation) is, the cleanest way to separate them is by unit of analysis: SEO optimises the page, AEO optimises the passage, and GEO optimises the entity — your brand as the engines understand it across the whole web.

Dimension	SEO	AEO	GEO
Primary goal	Rank in organic results	Be selected as the direct answer to a question	Be named, cited and recommended inside generative AI answers
Main surface	Google and Bing result lists	AI Overviews, featured snippets, voice assistants	ChatGPT, Perplexity, Claude, Gemini
Unit of optimisation	The page and the domain	The passage — a section that answers one question	The entity — the brand itself
Core tactics	Technical SEO, topical content, backlinks	Direct answers, Q&A structure, lists, tables, schema	Entity clarity, quotable evidence, digital PR, unlinked mentions, reviews
Off-page signals	Inbound links and domain authority	Source authority and trustworthiness	Brand mentions anywhere — the “mention graph” is the new link graph
Success metric	Rankings, impressions, clicks	Answer presence and citation rate	Mention rate and share of voice across repeated prompts

The practical implication is that a brand can rank #1 in Google (SEO success), appear in an AI Overview for one query (AEO success), and still be absent when a buyer asks ChatGPT to recommend vendors (GEO failure). The layer that fails is the one that loses the deal — which is why agencies increasingly sell all three as a combined AI-search programme. Underpinning it all is solid SEO: Google is explicit that there are no special technical requirements for AI Overviews — a page must be indexed, snippet-eligible and technically sound, which makes SEO the prerequisite rather than the casualty.

Why does GEO matter for UK agencies in 2026?

Three shifts make GEO commercially urgent rather than speculative:

• AI answers are everywhere. Independent studies place Google AI Overviews on roughly 15–30% of search queries, with higher rates for informational and commercial-investigation intents, according to Technology.org’s GEO guide. When an Overview appears, clicks to organic results below fall sharply — while the sites cited inside the answer collect a disproportionate share of what remains.
• Buyers shortlist vendors inside chatbots. ChatGPT passed 800 million weekly active users in 2025, and Perplexity answers tens of millions of queries daily. Analytics platforms now track AI referrals as a distinct channel — and in many B2B accounts it already outperforms long-tail organic search on lead quality.
• Recommendations happen before the search. Users increasingly research products inside generative engines before ever opening a search engine. If ChatGPT recommends three agencies and yours isn’t named, you were never in the room. Ranking #1 in Google doesn’t fix that.

There is also a first-mover window. Practitioner research suggests most enterprise marketing teams launched some form of GEO initiative by early 2026, while the majority of smaller businesses haven’t started — which means the agencies selling GEO services now are educating a market with very little entrenched competition. Curious what a GEO baseline looks like for your client portfolio? Book a free 30-minute consultation and we’ll show you exactly which prompts your brands are invisible in.

The five pillars of GEO

A working GEO strategy rests on five areas of competence, summarised here from the practitioner consensus (including the framework laid out in Technology.org’s guide). Each one maps to how generative engines actually build answers.

1. Semantic content architecture — write to be quoted

Generative engines parse meaning, not keywords. GEO-ready content is built around clearly defined entities, claims and relationships: explicit definitions, structured headings, FAQ blocks, comparison tables and statements written so an LLM can extract and quote them directly. The goal isn’t “to be ranked” — it’s “to be quotable”. Every key page should open with a self-contained 40–60 word answer before expanding, because that’s the unit engines lift.

2. Citable evidence and factual density

Engines prefer to cite content with specific, verifiable, sourced claims. A page that says “we’re a market leader” offers nothing extractable; a page that states its method, attributes its numbers and links to primary sources gives the engine exactly what it needs. This is the direct lesson of the Princeton paper: adding citations, quotations and statistics measurably raised visibility. Raising the factual density of every commercially important page is among the highest-leverage GEO tactics available.

3. A distributed mention graph — digital PR and citation building

Because LLMs train on the open web — and many retrieve from it in real time — visibility in third-party content directly influences citation rates. An unlinked brand mention in a Reddit thread, an industry publication, a podcast transcript or a review site can tip whether an engine names you — a break with twenty years of SEO logic, where unlinked mentions carried little value. Digital PR, expert contributions, directory listings and genuine reviews now belong to GEO: the mention graph is the new link graph. Engines treat corroboration across independent sources as the strongest trust signal there is.

4. AI-crawler accessibility

Generative engines run their own bots — OpenAI’s GPTBot and OAI-SearchBot, PerplexityBot, Anthropic’s ClaudeBot, Google-Extended — each of which can be allowed or blocked in robots.txt. The hygiene checklist: don’t accidentally block AI crawlers, keep key content in plain server-rendered HTML, maintain fast load times, and keep entity-defining pages one or two clicks from the homepage. Technical SEO skills transfer directly here — applied to a different set of user agents.

5. Prompt-based measurement

GEO has no single dominant analytics platform, so practitioners combine dedicated AI-visibility tools (such as Profound, AthenaHQ or Otterly), manual prompt testing against commercially important queries, and custom GA4 channels isolating AI-referral traffic from domains like chat.openai.com and perplexity.ai. A minimum stack tracks share of voice across at least four engines every week — because AI answers change on nearly every run, and a single prompt is never evidence.

The GEO playbook: eight steps for agencies

Here’s how the pillars translate into an agency-ready delivery sequence — work that AI-enabled delivery teams and SEO specialists can run for clients week in, week out:

1. Map the prompts that matter. Start with buying questions, not keywords. List the 20–50 prompts a prospect would ask before hiring and test each across ChatGPT, Perplexity, Gemini and Google AI Overviews. Document who’s cited. That’s your baseline; repeat monthly.
2. Define the entity, everywhere. Engines build a picture of your brand from every page, profile and listing that mentions it. State what the business is, who it serves and where, in the same terms on the website, directories, review platforms and social profiles. Inconsistent information makes engines trust none of the sources.
3. Rewrite priority pages for extraction. Lead each service page and key post with a direct, self-contained answer; replace vague claims with sourced facts; add comparison tables and question-based headings. One well-structured page can be cited across dozens of prompts for years.
4. Add the three credibility upgrades from the research. Cite authoritative sources, include direct quotations with named credentials, and support claims with statistics. The paper’s finding is blunt: credible-looking content gets cited more — keyword stuffing does not help.
5. Implement schema that mirrors visible content. Organisation, Article, FAQPage, HowTo and Person markup (schema.org) helps machines disambiguate entities — but only when it describes what’s actually on the page. There is no magic “AI schema”, and Google says none is required for AI Overviews.
6. Build the mention graph off-site. Run digital PR for expert quotes and bylines, earn reviews on platforms buyers check, keep directory listings accurate, and contribute genuinely to communities. Every independent mention is a vote an LLM can corroborate.
7. Fix the technical layer. Audit robots.txt for AI crawler blocks, ensure critical pages render server-side, speed them up, and use descriptive internal links. If your clients’ SEO foundations are weak, GEO has nothing to stand on.
8. Measure, then iterate. Track citation rate and share of voice per prompt across engines, monitor AI-referral traffic in GA4, and report visibility as a percentage across many runs — never as a single “position”.

GEO rewards consistency, not heroics. The agencies winning AI citations aren’t doing one clever trick — they’re publishing quotable, evidence-rich content and building their mention graph every week. If your team can’t staff that cadence for every client, talk to Spurtech: our Growth Agents run content, optimisation and AI-visibility monitoring under your brand, at one flat monthly rate per agent quoted on the call.

How do you measure GEO success?

AI answers are non-deterministic — the same prompt can return different citations on every run — so measurement has to be statistical, not positional:

• Prompt-level share of voice. Run a fixed list of commercial prompts weekly across ChatGPT, Perplexity, Gemini and AI Overviews; record citation rate per prompt and report the percentage across many runs.
• AI-referral analytics. Isolate AI-domain traffic in GA4 (chat.openai.com, perplexity.ai, claude.ai, gemini.google.com). It’s typically small but converts well, because the AI has pre-qualified the intent.
• Citation accuracy. Being named isn’t enough if the engine describes you wrongly — misattribution is a prompt to fix your entity definitions.

Never report a single prompt run as a “ranking”, never promise guaranteed citations, and always tie GEO reporting to pipeline — the question that matters is whether AI-cited buyers become consultations.

Common GEO mistakes to avoid

• Treating GEO as a replacement for SEO. Generative engines retrieve from the same indexes as search engines — pages that aren’t crawled, indexed and ranking won’t be cited either.
• Chasing magic files and “AI schema”. No markup guarantees entry to AI answers, and Google is explicit that none is required for AI Overviews. Conventions like llms.txt are optional at best.
• Keyword stuffing and scaled thin content. The Princeton research found keyword stuffing did not improve generative visibility — and Google’s spam policies now explicitly cover AI Overviews and AI Mode.
• Publishing thin “GEO pages” for every query. Engines reward information gain — content that adds something genuinely new — not question-stuffed pages with nothing to say.
• Neglecting off-page work. The most common GEO failure is a brand with decent content that nobody talks about. Without the mention graph, engines have no corroboration to trust.
• One engine, one run, one conclusion. AI visibility is a distribution across engines and runs. Measure broadly and repeatedly, or you’ll optimise for noise.

Offering GEO as a white-label service

Here’s the agency angle most guides skip: GEO is sellable right now, and it’s a natural extension of work many agencies already deliver. Prompt research, quotable content, schema, digital PR and citation monitoring are SEO-adjacent disciplines — packaging them as an “AI search visibility” service gives clients a clear reason to increase retainers. Pair it with our AEO guide and you have a complete answer-engine offering.

The barrier is delivery capacity. GEO rewards consistent, labour-intensive production: quotable content every week, prompt-level monitoring across engines, relentless mention-graph building. Most agencies can’t staff that for every client without hiring — and white-label delivery exists for exactly this. Spurtech’s dedicated Growth Agents plug into your agency and run SEO, AEO and GEO programmes under your brand — content, optimisation, digital PR support, AI-visibility monitoring and reporting. You keep the client relationship and the margin; we do the work.

The commercial model is deliberately simple: each agent works 8 hours a day, Monday to Friday, under your brand, at one flat monthly rate per agent — quoted on a free 30-minute consultation, never published as a fixed price. Full detail on how the model works is on our pricing page, and answers to common questions are on our FAQs. To understand the delivery engine behind our GEO work, see how an AI automation agency works.

GEO FAQs

What does GEO stand for?

GEO stands for Generative Engine Optimization — Generative Engine Optimisation in British English. It’s the practice of optimising a brand’s content, entity signals and online reputation so that generative AI engines cite, quote or recommend the brand inside their synthesised answers.

Who coined the term “generative engine optimization”?

The term was introduced in November 2023 in the academic paper GEO: Generative Engine Optimization (arXiv:2311.09735) by Pranjal Aggarwal, Vishvak Murahari, Tanmay Rajpurohit, Ashwin Kalyan, Karthik Narasimhan and Ameet Deshpande — researchers from Princeton University, Georgia Tech, the Allen Institute for AI and IIT Delhi. The paper was later accepted at KDD 2024.

What is the difference between GEO and AEO?

GEO optimises at the level of the entity — whether AI systems trust your brand enough to name, cite and recommend it across the whole web. AEO optimises at the level of the passage — whether a specific section of your content is extracted as the direct answer to a question. They’re complementary: AEO gets you selected as an answer; GEO gets you recommended as a vendor. Our AEO guide covers the passage-level discipline in depth.

Does GEO replace SEO?

No. Generative engines retrieve from the same web indexes as search engines, and Google states there are no additional technical requirements for AI Overviews — pages must be indexed, snippet-eligible and technically sound. GEO is a layer on top of strong SEO: SEO gets you retrievable, AEO gets you extractable, GEO gets you recommended.

How do I get my brand cited by ChatGPT and Perplexity?

Rank well in traditional search (AI citations overlap heavily with organic rankings), define your business entity consistently everywhere, write quotable content with sourced facts and expert quotations, use schema that mirrors visible content, earn independent mentions through digital PR and reviews, keep AI crawlers unblocked, and measure citation share across engines weekly.

How long does GEO take to work?

Honestly: it depends on the engine and your starting authority. Google AI Overviews can reflect content changes within weeks since they retrieve from live indexes; training-data-dependent systems like ChatGPT and Claude absorb new information more slowly. Expect leading indicators (citation share across tracked prompts) within one to three months, and treat GEO as a compounding programme — every quotable page and earned mention is retrievable source material for years.

The bottom line: GEO is the discipline of being recommended, not just being found. The agencies that master it now will own the client conversation about AI search for the next decade. Book your free 30-minute consultation and let’s map out what AI-engine visibility — delivered white-label under your brand — could do for your client roster.