GEO · Generative engine optimisation
GEO Agency: Ensure your brand is visible in AI search
Castle International’s generative engine optimisation service ensures your brand appears in AI search responses. As a specialist GEO agency, we help AI search engines like ChatGPT, Perplexity and Google’s AI overviews cite and recommend your brand correctly, building the authority signal AI platforms rely on to ensure your cited favourably against competitors.
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A specialist GEO agency
Being visible in AI search is only half the battle.
Getting your brand cited in AI search is not enough, what AI platforms say about your brand matters just as much. Generative engine optimisation (GEO) helps to shape how your brand is understood by large language models (LLMs) and what AI search says about you. This means helping AI platforms recognise what you do, which products or services you should be known for, which competitors you’re grouped with and why your business deserves to be recommended ahead of them.
This is built from more than just what your website says. AI search draws on information across the wider web, including what third-party sources say about you, how your brand is described, and how easily it can tell your brand apart from similarly named things. Castle’s GEO service works on strengthening these signals. We build a clearer, more consistent and authoritative presence across your website and the wider web to increase your chances of being found, cited and recommended in AI search.
What’s included
What’s included in our GEO services
Castle provides a managed generate engine optimisation programme aimed at providing presence, accuracy and share of voice inside AI-generated answers.
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Brand AI representation audit
We assess how large language models (LLMs) describe your brand, compare you to competitors and where they’d recommend you, if at all. We record and review what they actually say about you and identify citation gaps, inconsistences, errors and outdated claims, as well as the competitors they recommend over you. This helps us determine the steps that come next.
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Entity and knowledge signals
Castle makes your brand unambiguous, ensuring consistent naming, descriptions and categories across your site, profiles and third-party sources LLMs lean on, adding Organisation and Product markup where needed so the entity resolves to you rather than something with a similar name.
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Source material models can use and cite
Generated answers cite phrases they find. We create, refine and restructure content for GEO purposes, so that your content is findable and quotable by AI models and the phrase generative search uses is yours.
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Third-party evidence and presence
AI search engines weight what third-party sources say about you more heavily that what you say about yourself. Citations from established news sites, industry directories or journals give you high authority in AI search. We build the reviews, directory enquiries, digital PR and community presence that AI engines can use to corroborate your brand.
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Competitive share of voice
Our GEO specialists track how often you appear compared to named competitors across the prompts that matter and then optimise your content to fill the gaps where you are missing from comparisons and the categories where a competitor is consistently cited before you.
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Monitoring and correction
As AI models are retrained, their responses can change. We regularly monitor how your brand appears across AI platforms, re-running prompts on a schedule to check how your business is being described and catch inaccurate or outdated descriptions early. Our GEO team then strengthen the signals that help AI platforms understand, trust and recommend your business.
Why GEO
Why do I need a GEO agency?
You can be cited in AI search and still lose out to competitors. If AI models describe your service incorrectly, price your products inaccurately or frame you as the worse option next to a rival, then this mention works against you. GEO is the about increasing your AI visibility as well as determining what is said about you.
AI search engines don’t rely on your website alone to build a picture of your brand. They use information from across the web to understand who your business is, what you offer and how you compare with other brands. The fix for a bad description is usually off-site, such as inconsistent business information, an outdated directory entry or a lack of positive reviews.
Our GEO services help strengthen that digital footprint. We identify inaccurate, inconsistent or outdated information and look for opportunities to build the authority and relevance AI platforms need to confidently understand, cite and recommend your business in the answers your customers are actually searching for.
At Castle we run GEO alongside answer engine optimisation (AEO) and traditional search engine optimisation (SEO), so presence, citation and ranking are one programme rather than three, designed to build your brand visibility across both conventional and AI-powered search.
Traffic arriving from AI answers converts far better than standard organic. Ahrefs reports AI traffic converting 23x more than organic search — just 0.5% of traffic generating over 12% of signups. Traditional SEO converts around 2.1–2.8%; AI referrals are reported at 14.2–27%.
AI search platforms
Which generative platforms we optimise for
Every AI search platform interprets and recommends brands in different ways. Our GEO strategies are designed to increase your visibility across all the platforms your customers are using.
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ChatGPT
We optimise your brand’s presence to help ChatGPT understand what you offer, accurately representing your business to increase your chances of appearing in relevant answers.
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Google AI Overview and AI Mode
We combine GEO with technical SEO, content optimisation and authority building to help your business earn greater visibility across Google’s AI-generated search experiences.
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Perplexity
With citations at the heart of Perplexity’s answers, we focus on strengthening the authoritative sources and content that can help your brand become more visible and frequently cited.
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Microsoft Copilot
We strengthen the authority and consistency of your presence across the sources Copilot relies on, so its summaries of your business stay accurate.
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Google Gemini
We build clear entity and topical signals so Gemini can place your brand in the right category and generate a description that reflects what you actually offer.
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Claude
Claude tends to describe a business in its own words rather than repeat a strapline, so what it says depends on the substance available. We work on the material behind the summary — how you are positioned, compared and qualified across the web.
Our goal across every platform is to not only make your brand easier to find in AI search but ensure what it cites is accurate and beneficial to your business. Presence without accuracy is not a win, so we report on what each platform says as well as how often it says it.
Industries we have worked with
GEO strategies built for your industry
How people use AI search varies considerably between industries. How people search and what sources influence AI recommendations can vary between industries.
That's why we don't take a one-size-fits-all approach to GEO. We build strategies around your industry, your audience and answer the questions potential customers are asking throughout their search journey. We identify the content and authority signals that matter most in your sector to help your brand become more visible and trusted across AI search platforms.
Some of the sectors we’ve previously worked with include:
- SaaS
- Ecommerce
- Finance
- Healthcare
- Property
- Legal
- Education
- Professional services
- Technology
- Travel and hospitality
GEO is the future of search
Why does my brand need GEO now?
- 900MWeekly active ChatGPT users
- 1BNGoogle AI Mode monthly users
- 2028When AI search may pass traditional search
Models are forming a description of your brand right now, from whatever material happens to exist. If you have not deliberately supplied that material, the description is an accident.
Corrections are slow. Once an inaccurate or unflattering characterisation is established across the sources a model trusts, shifting it takes months of signal-building, which is why it is best to get ahead of it and build the image you want of your brand first rather than repairing it later.
The audience is already at scale: ChatGPT reports over 900 million weekly active users, Google AI Mode passed a billion monthly users in May 2026, and Semrush suggests AI search traffic may overtake traditional search by 2028.
The behaviour has changed too. Instead of “best skincare brand”, people ask AI search “what’s the best skincare brand for sensitive skin under £30?”, a question that returns a shortlist with reasons, and your place on it is a GEO outcome.
AEO gets you cited. GEO decides whether the sentence you are cited in sells your brand effectively.
GEO specialists
Why choose Castle as your GEO agency
We have been optimising search for over 15 years and have already helped clients gain visibility across every leading AI platform, including ChatGPT, Perplexity, Claude, Gemini and Copilot.
Our GEO service includes the off-site work most other agencies skip, the digital PR, review building and directory consistency, roundups, and a deliberate Reddit and Quora presence, because that is where a model gets the corroboration it needs before it recommends anyone.
We report on share of voice against competitors you choose, and on what the models actually say, so you can see the description improving rather than just a generic visibility score. As a leading GEO agency and generative engine optimisation company in the UK, we’re well placed to manage your GEO, AEO and AI search visibility end to end.
FAQ
GEO frequently asked questions
Generative engine optimisation is the practice of influencing what AI models say when they write about your market — whether your brand appears, how it is described, which products get named and who you are compared with. It works on your entity signals, the source material models can reuse, and the third-party evidence they weight most heavily.
AI SEO is the umbrella. It brings together GEO, AEO and traditional SEO fundamentals into one programme. GEO is specifically the generation side: presence and representation inside the answer. If you want the full managed service across all three, that is our AI SEO offer.
AEO is about being retrieved and cited — getting your page into the answer. GEO is about what the answer then says about you. A brand can be cited and still described badly, or described well and rarely cited. Most clients need both, which is why we run them together.
You can change the inputs, which changes the output over time. Models generate from the material available to them, so making your positioning explicit and quotable, resolving your entity cleanly, and building corroborating third-party sources all shift the description. It is influence rather than direct control, and it is not instant.
With a fixed prompt set, re-tested on a schedule: whether you appear, how you are described, which competitors appear beside you, and your share of voice across the set. We log the actual model output each time so changes in wording are visible, not just changes in a score.
Early movement — new mentions, corrected details — typically shows within four to eight weeks. Shifting how you are characterised in competitive categories takes three to six months, because it depends on off-site signals accumulating.
Yes. Google still handles the majority of search volume, and pages that rank are more likely to be retrieved and reused by models in the first place. We build GEO on top of solid traditional SEO rather than treating them as separate budgets.
ChatGPT, Google AI Overviews and AI Mode, Perplexity, Microsoft Copilot and Google Gemini, with Claude included in tracking where it is relevant to your market.
Get started
See how AI currently describes your brand
We will run your market’s prompts across the major models and send you the raw output — what they say about you, and who they name instead.