Short answer
Topical authority is how completely and credibly a site covers a subject, so search engines and AI assistants keep finding it useful for that subject. Google describes a topic authority system only for news, but its guidance asks every site for focus and expertise, and 2026 studies link topic coverage with AI citations and mentions. You build it by mapping the questions behind a subject, giving each intent one strong page, and adding what only you know.
Key takeaways
- Topical authority is an industry term for how completely and credibly a site covers a subject; the one system Google has described under that name serves news.
- Google’s guidance for other sites points the same way: a primary purpose or focus, first-hand expertise, and no content on many different topics in the hope that some of it performs.
- In Wellows’ 2026 study of 9,471 questions, topic coverage tracked AI citations more closely than a stored domain authority score on four of five engines.
- In Semrush’s ChatGPT study, only 15.2% of 1,094 categories had a clear owner, so most subjects are still open.
- Build it with one strong page per intent, hub and spoke links and content only you can write; Google treats a page for every search variation, made to manipulate results, as scaled content abuse.
What topical authority means
Topical authority is how completely and credibly a site covers a subject. It is an industry term, and it describes a result: when someone asks about that subject, search engines and AI assistants keep finding the site useful. It sits where SEO and AI search overlap, which I cover in my comparison of answer engine optimization, generative engine optimization and SEO.
The one system Google has described under that name serves news. Its topic authority system looks at how notable a source is for a topic or location, how other publishers cite its original reporting, and its reputation, such as a history of high-quality reporting or recommendations from professional societies [1].
For other sites, Google’s guidance points the same way without using the term. Its self-assessment for helpful content asks whether your site has a primary purpose or focus and whether the content shows first-hand expertise, and it lists producing lots of content on many different topics, in the hope that some of it performs, as a warning sign [2].
Why AI search rewards coverage of a subject
AI answers are built from retrieval. Google’s AI features run query fan-out, a set of related searches the model generates to fetch more results: a question about fixing a lawn full of weeds also searches for the best herbicides and for how to prevent weeds. The systems then review the retrieved pages to write the response [3]. In Ahrefs’ study of about 4 million AI Overview URLs, 38% of the cited pages ranked in the top 10 for the same query, which leaves most citations coming from outside it [7].
A site that answers the whole subject matches search after search inside that fan-out, and I explain the mechanism in how query fan-out works.
Focus also changes how a brand appears in the answer. In Semrush’s study with Kevin Indig of 1,094 categories in ChatGPT, brands in categories close to their core expertise were cited in 74% of their appearances, named in 44% and both in 34%. In distant categories those shares fell to 50%, 25% and 9% [5]. Close to home, a brand is more often named as well as linked.
What the 2026 studies show
Wellows compared 9,471 questions across five engines, collected from January to May 2026. It measured how much of a topic each site was cited for on one half of the questions, then checked that against the site’s citations on the other half [6]. Coverage tracked those citations more closely than a stored domain authority score on four of the five engines, and the two were about level on Gemini [6].
| Engine | Topic coverage | Domain authority score |
|---|---|---|
| Google AI Overviews | 0.29 | 0.22 |
| Google AI Mode | 0.28 | 0.22 |
| Perplexity | 0.25 | 0.15 |
| Gemini | 0.20 | 0.21 |
| ChatGPT | 0.13 | 0.10 |
These are modest correlations, and the strongest measure in the study was a third one: how often a site was cited on other topics, at 0.29 to 0.37 [6]. The authors state that the figures are associations, which do not establish a ranking factor or show what happens when you publish more pages [6].
Semrush’s study of 50,000 brands looked at who owns a topic in ChatGPT, meaning one brand named in at least four of five prompts with a lead of five points or more. Only 15.2% of the 1,094 categories had a clear owner and 53.7% were unsettled; among the topics people ask about most, 11.3% had an owner [4]. Owners beat the runner-up on Authority Score in 52.5% of pairs and on organic traffic in 48.4%, close to a coin flip, and clear owners stayed first in 90.4% of month-over-month comparisons [4]. The study covers ChatGPT and US categories only, and both Semrush and Wellows sell AI visibility tools.
Read together, the data says most subjects are still open, an established domain is no guarantee of owning one, and a clear lead tends to hold.
How to build topical authority, step by step
- Choose the subject, narrow enough to own and close to what you actually do. Google’s guidance asks for a primary purpose or focus [2].
- Collect the questions behind it: the main keywords, the fan-out searches and the follow-ups your buyers ask [3].
- Group them by intent. Each intent gets one main keyword and one page, and the supporting questions become sections on that page.
- Map your existing pages and your top 20 competitors against that set, to see what is missing, thin or doubled.
- Organize the pages as hub and spoke: a pillar for the subject and a page per intent, with internal links, menus and URLs following the same structure.
- Write what only you can write: first-hand experience, your own data, your own examples. Google calls this non-commodity content and says it will likely influence your presence in generative AI search more than any other suggestion in its guide [3].
- Earn mentions and links beyond your own pages through digital PR, since being cited beyond one topic had the strongest correlation in Wellows’ data [6].
- Keep the subject current: track how often you publish and refresh, and update pages as the subject moves.
Step 3 carries the most weight. The plan I build for clients puts every page in one of four tiers, which set its depth, its internal links and its on-page structure, so the whole subject reads as one body of work. The keyword research and content planning page shows how that runs.
What spreads authority thin
More pages are the common mistake. Google warns that creating separate content for every variation of how people might search, fan-out queries included, violates its scaled content abuse policy when it is done primarily to manipulate results, and adds that a high quantity of pages doesn’t make a website higher quality or more relevant [3]. Its self-assessment also asks whether you entered a niche topic without real expertise, mainly for the search traffic [2].
Depth inside a subject pays. In Semrush’s data, a brand that appeared in one of five prompts in a category had a lower share of mentions, and that penalty disappeared at three of five [5]. Answer a subject’s main questions fully before you move on to the next subject.
The same reasoning is why I don’t run programmatic SEO: it carries real risk and rarely delivers the growth people expect.
How to measure topical authority
Track what topical authority should produce, one subject at a time.
- Share of voice by subject: how often assistants name and cite you across a fixed set of prompts, as I set out in how to measure AI search visibility.
- Prompt coverage: Semrush’s bar for an owner, named in at least four of five prompts with a lead of five points, makes a clear target [4].
- Fan-out coverage: how many of the searches behind your priority questions your pages rank for.
- Non-branded search: impressions and clicks for each topic in Search Console.
The tools I build track these across competitors. On one program for a leading news portal, share of voice in AI answers rose from 9% to 41% against the top 5 competitors, with more than 120 queries moving into cited positions through entity coverage.
A worked example: a payroll software company
The company and its numbers here are illustrative. A payroll software company has 140 blog posts across HR, marketing, productivity and payroll. Across five prompts about payroll for small businesses, ChatGPT names it in one.
The team picks payroll for small businesses as the subject and collects 90 questions and fan-out searches, which group into 15 intents. It merges 30 overlapping posts, retires the ones far from the subject, and builds a pillar with 14 supporting pages, linked as hub and spoke. It adds what only it has: anonymized data on the payroll errors its customers fix most. Two quarters later, ChatGPT names it in four of the five prompts, and the team moves on to the next subject.
Frequently asked questions
What is topical authority?
It is how completely and credibly a site covers a subject, so that search engines and AI assistants keep finding it useful for that subject. The term comes from the SEO industry, and the one system Google has described under that name serves news.
Is topical authority a Google ranking factor?
Google describes a topic authority system for news, with signals such as how notable a source is and how other publishers cite its reporting. For other sites, its guidance asks for a primary focus and first-hand expertise. The 2026 studies show associations with AI citations, which stop short of a proven ranking factor.
How many articles do I need for topical authority?
There is no set number. Cover each search intent in the subject once, with one strong page, and answer the supporting questions inside it. Google warns that a high quantity of pages doesn’t make a website higher quality or more relevant.
How long does topical authority take to build?
It depends on how contested the subject is and how much of it you already cover, so track it monthly. In Semrush’s ChatGPT study, the top brand often changed where leads were small, while clear owners stayed first in 90.4% of month-over-month comparisons.
Does topical authority replace backlinks?
They work together. In Wellows’ study, a stored domain authority score also tracked AI citations, and being cited beyond one topic tracked them most closely. Links and mentions from other sites build that reach, and your coverage gives them something worth pointing to.
Sources
- Google Search Central Blog, “Understanding news topic authority”, 23 May 2023. developers.google.com
- Google Search Central, “Creating helpful, reliable, people-first content”, last updated 5 October 2026. developers.google.com
- Google Search Central, “Google’s guide to optimizing for generative AI features on Google Search”, last updated 10 July 2026. developers.google.com
- Semrush, Margarita Loktionova with Kevin Indig, “AI visibility is a topic-level game: A study of 50,000 brands in ChatGPT”, 20 July 2026. semrush.com
- Semrush, Margarita Loktionova with Kevin Indig, “How topical authority spreads (and where it doesn’t) in ChatGPT”, 3 August 2026. semrush.com
- Wellows, Khadija Zaman, “Does Topical Authority Show Up in AI Citations? What 9,471 Questions Reveal”, 28 September 2026, updated 7 October 2026. wellows.com
- Ahrefs, “Update: 38% of AI Overview Citations Pull From The Top 10”, 2 March 2026. ahrefs.com