GEO explained: how brands get cited by ChatGPT, Gemini and Perplexity
Generative Engine Optimization is the discipline of becoming the source AI engines quote. Here is what it involves, how it differs from SEO and what a credible programme costs.
When a buyer asks ChatGPT which clinic to book, which software to try or which supplier to call, the answer names two or three brands and cites a handful of sources. If you are not one of them, you were never in the running. Generative Engine Optimization, or GEO, is the work of making sure you are.
How AI engines decide who to cite
Large language models do not rank pages the way Google does. They retrieve candidate sources, usually via a search index, then synthesise an answer and attribute claims to the sources they trust most. Trust is built from a few signals: whether the model can resolve who you are as an entity, whether your content makes clear, checkable claims, and whether independent sources already mention you in the same context.
The five pillars of a GEO programme
- AI visibility audit: run hundreds of real buyer prompts across engines and map where you appear, who is cited instead, and why.
- Entity and knowledge graph work: consistent brand, product and people data across your site, directories, Wikidata and profiles.
- Structured, quotable content: answer-first pages with definitions, statistics, comparisons and FAQs, backed by schema and llms.txt.
- Third-party presence: placements in the listicles, review sites, communities and publications models already draw from for your category.
- Measurement: share of answer per engine and per topic, tracked monthly, alongside AI-referred traffic and leads.
GEO vs SEO
They share foundations. Technical health, authority and good content help both. But SEO is measured in rankings and clicks, while GEO is measured in citations and share of answer. GEO also leans much harder on third-party mentions, because a model that sees your brand recommended in ten independent places will recommend it too. Most brands should run both from one roadmap.
What it costs, honestly
Agency GEO retainers in 2026 range from around $1,500 to well over $20,000 per month. Programmes under $3,000 are usually classic SEO with a new name. Credible mid-market work sits between $3,000 and $25,000 depending on how competitive the category is and how much third-party placement and PR is involved. Our own plans start at $2,500 for foundations and $5,500 for a full authority programme.
The question is no longer 'where do we rank'. It is 'when a customer asks, are we the answer'.
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