GEO vs SEO: what actually differs, and what does not

Where do GEO and SEO collapse into one job?

On Google's own AI surfaces. Google states there are no additional requirements to appear in AI Overviews or AI Mode, nor other special optimisations necessary. To appear as a supporting link, a page must be indexed and eligible to be shown in Google Search with a snippet. Google adds that you don't need new machine-readable files, AI text files or markup, and that there is no special schema.org structured data to add.

So for AI Overviews and AI Mode, GEO is SEO. A separate "GEO checklist" for Google's AI features is a checklist for something Google says does not exist. The controls that limit inclusion are the SEO ones too: whether a page is indexed and whether it may be shown with a snippet.

That is also why most GEO advice reads like SEO advice. The ChatGPT answer at the top of this page describes GEO as optimising content to be "found, understood, and cited", and later in the same answer it calls GEO "more like an extension of SEO", pointing to Google's statement that foundational SEO practices remain important for generative AI experiences.

Where do they genuinely differ?

On the engines that fetch the web themselves: ChatGPT search and Perplexity, among others. Four things change.

Crawlers. Each engine has its own crawler and its own robots.txt token, such as OAI-SearchBot for ChatGPT search and PerplexityBot. A site that is perfectly crawlable by Googlebot can block all of them by accident, usually through a blanket rule written to keep out AI training crawlers. SEO never had to check these lines.

Passages. An answer quotes passages, not pages. A paragraph that only makes sense after the three before it is hard to lift. GEO work often means rewriting key sections so each answers one question on its own, with its numbers and their sources inside it.

Third-party presence. For shortlist questions, engines lean on pages that compare and recommend: vendor blogs, review sites, community threads, trade press. A brand absent from those pages is hard to recommend however good its own site is. This is closer to PR than to on-page work.

Measurement. Rankings do not tell you whether an answer names you. You have to ask the engines your buyers' questions on a schedule and record what comes back, per engine, with the number of answers behind each rate.

What does our own data show about the overlap?

That SEO authority carries into AI answers, and that it is not the whole story. We track 61 prompts about AI search for our own brand on ChatGPT and Perplexity. One of them is the head question of this page, "what is generative engine optimization", answered 108 times in the 30 days to 4 October 2026.

When ChatGPT answered it, it read SEO documentation. Its 60 answers carried 1,915 citations, and 708 of them pointed at Google's Search Central pages. The Princeton page for the paper that coined GEO carried 42. When either engine named a brand in the answer, the one named most often was Semrush, an SEO suite, in 22 of 108 answers. Across everything we track, the 4,524 answers carried 100,380 citations, and Google's developer documentation and semrush.com were among the most-cited domains, with 4,381 and 2,240. Perplexity leaned on the same kind of source: HubSpot's blog carried 63 of the 477 citations in its 48 answers, and semrush.com 31.

The same data shows the limit. Our own GEO explainer was linked in 3 of those 108 answers, all on ChatGPT, and in none of Perplexity's 48. This page was fetched 58 times by AI crawlers in the same 30 days. Being fetchable got us into the answer occasionally; being the source older, more-linked sites already are is what gets a page chosen repeatedly. That is SEO's old lesson, applied to a new surface.

What does the GEO evidence actually say?

That structure helps and that results vary. The GEO paper reports that its methods can boost visibility by up to 40% in generative engine responses on its benchmark, GEO-bench, and that effectiveness differs by domain, which is why it argues for domain-specific methods. That is a real finding about a specific corpus, not a promise for your site.

SEO has no single headline figure of that kind. Google's guidance says some changes take effect in a few hours and others take several months, which is the honest framing for both disciplines: slow, cumulative and hard to attribute to one edit.

How long does each take to show?

Similar timescales, different signals. Google says SEO changes can take from a few hours to several months to be reflected. GEO changes depend on each engine re-fetching the page and then choosing it: a crawler may fetch within days, but a change in how often answers name or cite you needs weeks of daily readings before it clears the noise. In both cases, judge a change on weeks of data, not on a single search or a single answer.

What should a team that already does SEO do first?

Five checks, in order, each cheap. First, read your robots.txt as an AI crawler would: find every rule that names or catches OAI-SearchBot, PerplexityBot and the other search agents, and make sure a rule meant for training crawlers is not blocking the ones that put you in answers. Second, list the ten questions a buyer asks before shortlisting you and put each one to ChatGPT and Perplexity, reading the answers rather than skimming for your name. Third, for every answer that leaves you out, note which pages it cited; those are the third-party pages to be on. Fourth, pick the two or three pages of yours that engines already fetch and rewrite their key sections so each answers one question on its own. Fifth, keep reading the same questions daily for a few weeks before you judge anything.

None of these replaces an SEO task. They sit on top of a site that is already indexed, fast and well linked, which is why the order is SEO first and GEO on top.